Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Jonas Smedegaard]

Quoting Erik Josefsson (2019-06-23 15:42:05)
> On 6/23/19 8:40 AM, Jonas Smedegaard wrote:
> >> If random IO speed most likely is the real bottle neck, do you know 
> >> of any particular brand/label/kind/category of MicroSD card that is 
> >> significantly better than others in that regard?
> > https://github.com/ThomasKaiser/Knowledge/blob/master/articles/A1_and_A2_rated_SD_cards.md
> >
> > (this is perhaps 5th time I share that link with you; 2nd on this 
> > list)
> 
> The article by Thomas Kaiser ends with an open discussion that you can 
> probably just as well buy A1 cards made before 2017.

You call a section labeled "TODO" an open discussion?  Oh well.


> The last card I bought is neither A1 or A2 but marked with a XC II 
> logo. That particular markup is not mentioned in Kaiser's article.

Maybe because the text is about A1/A2 classification, only briefly 
linking to the historic thread covering lesser relevant cards.


> So the article cannot tell me which of my 4 cards is likely to be the 
> best for my usecase:
> 
> MicroSD SanDisk Extreme PRO  64GB  [3]  XC II
> MicroSD SanDisk Extreme PLUS  64GB  [3]  XC I  V30  A2
> MicroSD SanDisk Extreme PLUS  32GB  [3]  HC I  V30  A1
> MicroSD SanDisk Ultra  32GB  [1]  HC I  (10)  A1

The section "'Application Performance Class' to the rescue" didn't help 
tell you about the relevancy of A1/A2 classification?

And subsection "Real world 2018 A1 and A2 performance comparison" didn't 
help tell you about real-world relevancy of A1 versus A2 classification?

Oh well.


> Ahh.. there's another hint! For some applications, disk partition 
> matters?

Explained here (yes, shared a few posts ago as well):

https://wiki.gentoo.org/wiki/SDCard#Solution_2:_Tuned_ext4
https://thelastmaimou.wordpress.com/2013/05/04/magic-soup-ext4-with-ssd-stripes-and-strides/
https://lists.linaro.org/pipermail/flashbench-results/2014-July/000479.html


 - Jonas

-- 
 * Jonas Smedegaard - idealist & Internet-arkitekt
 * Tlf.: +45 40843136  Website: http://dr.jones.dk/

 [x] quote me freely  [ ] ask before reusing  [ ] keep private


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Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Erik Josefsson]

On 6/23/19 8:40 AM, Jonas Smedegaard wrote:


Is it meaningful to test the SD cards with an USB-adapter? (the MicroSD
slot would be occupied by the SD card the machine is running from/on)

Testing SD cards on a different controller may help understand
_potential_  features of cards, but not_actual_  reachable potentials.

If you prefer an analogy: Reading in a magazine that some Formel-1
driver can cut a corner while driving 60km/h in same model car as yours
does not mean that you can expect to cut that same corner at that speed:
Depends not only on the vehicle (disk device) but also on the driver!



Sure. I have tried to drive the 4 cards along exactly the same path 
(i.e. flashbench) to reduce my influence on the performance. 
Unfortunately I cannot tell which one is the best from the resulting data.


If the fio benchmark can tell me which card is the best, I will try it 
at some point.






Of those figures, I consider the random ones more important in most
configurations. i.e. if I had to choose between a device that
supported a bit higher sequential read/write but much lower random
read/write, I'd rather have the random read/write, because that
tends to have more impact on interactive usage than sequential.

Yes, going back and forth between Thunderbird and Firefox while
copying text snippets from one app to the other sometimes ends in a
mouse pointer freeze.

That's basically what I do most of the time...

Biggest speed gain (on a limited computer like Teres-I) is likely had
with changing to less ressource hungry tools.

Instead of Firefox try GNOME Web (apt install epiphany-browser).  It
uses the rendering engine "Webkit" so is likely to handle most websites.
For an radically lighter browser rendering fewer real-world websites
properly and with an arguably less friendly user interface, try Surf.



This is very helpful. I have installed epiphany now. Thanks!



A lighter alternative with ok UI and somewhat decent rendering engine is
Netsurf, but unfortunately that one won't make it into Debian Buster.

Instead of Thunderbird try Balsa or Claws Mail.



OK. Thanks!






SD cards tend to have poor random IO speed so I would never use one
for general purpose computing if I could use an HDD or SSD instead.

If random IO speed most likely is the real bottle neck, do you know of
any particular brand/label/kind/category of MicroSD card that is
significantly better than others in that regard?

https://github.com/ThomasKaiser/Knowledge/blob/master/articles/A1_and_A2_rated_SD_cards.md

(this is perhaps 5th time I share that link with you; 2nd on this list)



The article by Thomas Kaiser ends with an open discussion that you can 
probably just as well buy A1 cards made before 2017. The last card I 
bought is neither A1 or A2 but marked with a XC II logo. That particular 
markup is not mentioned in Kaiser's article.


So the article cannot tell me which of my 4 cards is likely to be the 
best for my usecase:


MicroSD SanDisk Extreme PRO  64GB  [3]  XC II
MicroSD SanDisk Extreme PLUS  64GB  [3]  XC I  V30  A2
MicroSD SanDisk Extreme PLUS  32GB  [3]  HC I  V30  A1
MicroSD SanDisk Ultra  32GB  [1]  HC I  (10)  A1



Not sure if chasing some microseconds of better performance will make
a difference, but if it is anything like parking with a heavy truck
with heavy trailer in a small parking lot with other cars, then I
guess a microsecond extra is just as important as an extra centimeter
:-)



To give you some idea of what decent SSDs manage:

  
http://strugglers.net/~andy/blog/2019/05/29/linux-raid-10-may-not-always-be-the-best-performer-but-i-dont-know-why/


I don't think I can make Teres-I boot from an external SSD.

Through the USB2 interface you can.  Won't reach the full potentials of
SSD (see Formel-1 analogy above) but may still beat SD-cards.

You cannot_boot_  via USB2 interface but you can store your data there
which helps some scenarios (e.g. possibly helps Firefox hanging, as that
might be due to its working on cache data below your $HOME.



Ahh.. there's another hint! For some applications, disk partition matters?

I hope there is no downside to having two browsers installed, as long as 
you don't use them at the same time!


Best regards.

//Erik

Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Jonas Smedegaard]

Quoting Erik Josefsson (2019-06-23 07:42:24)
> Hi Andy, thanks for taking time and for your advise!
> 
> On 6/22/19 10:22 PM, Andy Smith wrote:
> > Hi Erik,
> >
> > On Fri, Jun 21, 2019 at 03:02:46PM +0200, Erik Josefsson wrote:
> >> Maybe flashbench cannot tell me anything about that anyway?
> >>
> >> Are there other tools?
> > I'm not familiar with flashbench. I like fio. It's available in
> > Debian.
> >
> > I like to do the following tests. Example fio command line follows
> > for each.

[ details snipped]

> Teres-I has one MicroSD slot, one HDMI and two USB ports.
> 
> Is it meaningful to test the SD cards with an USB-adapter? (the MicroSD 
> slot would be occupied by the SD card the machine is running from/on)

Testing SD cards on a different controller may help understand 
_potential_ features of cards, but not _actual_ reachable potentials.

If you prefer an analogy: Reading in a magazine that some Formel-1 
driver can cut a corner while driving 60km/h in same model car as yours 
does not mean that you can expect to cut that same corner at that speed: 
Depends not only on the vehicle (disk device) but also on the driver!


> > Of those figures, I consider the random ones more important in most 
> > configurations. i.e. if I had to choose between a device that 
> > supported a bit higher sequential read/write but much lower random 
> > read/write, I'd rather have the random read/write, because that 
> > tends to have more impact on interactive usage than sequential.
> 
> Yes, going back and forth between Thunderbird and Firefox while 
> copying text snippets from one app to the other sometimes ends in a 
> mouse pointer freeze.
> 
> That's basically what I do most of the time...

Biggest speed gain (on a limited computer like Teres-I) is likely had 
with changing to less ressource hungry tools.

Instead of Firefox try GNOME Web (apt install epiphany-browser).  It 
uses the rendering engine "Webkit" so is likely to handle most websites. 
For an radically lighter browser rendering fewer real-world websites 
properly and with an arguably less friendly user interface, try Surf.

A lighter alternative with ok UI and somewhat decent rendering engine is 
Netsurf, but unfortunately that one won't make it into Debian Buster.

Instead of Thunderbird try Balsa or Claws Mail.


> > SD cards tend to have poor random IO speed so I would never use one
> > for general purpose computing if I could use an HDD or SSD instead.
> 
> 
> If random IO speed most likely is the real bottle neck, do you know of 
> any particular brand/label/kind/category of MicroSD card that is 
> significantly better than others in that regard?

https://github.com/ThomasKaiser/Knowledge/blob/master/articles/A1_and_A2_rated_SD_cards.md

(this is perhaps 5th time I share that link with you; 2nd on this list)


> Not sure if chasing some microseconds of better performance will make 
> a difference, but if it is anything like parking with a heavy truck 
> with heavy trailer in a small parking lot with other cars, then I 
> guess a microsecond extra is just as important as an extra centimeter 
> :-)
> 
> 
> >
> > To give you some idea of what decent SSDs manage:
> >
> >  
> > http://strugglers.net/~andy/blog/2019/05/29/linux-raid-10-may-not-always-be-the-best-performer-but-i-dont-know-why/
> >
> 
> I don't think I can make Teres-I boot from an external SSD.

Through the USB2 interface you can.  Won't reach the full potentials of 
SSD (see Formel-1 analogy above) but may still beat SD-cards.

You cannot _boot_ via USB2 interface but you can store your data there 
which helps some scenarios (e.g. possibly helps Firefox hanging, as that 
might be due to its working on cache data below your $HOME.


 - Jonas

-- 
 * Jonas Smedegaard - idealist & Internet-arkitekt
 * Tlf.: +45 40843136  Website: http://dr.jones.dk/

 [x] quote me freely  [ ] ask before reusing  [ ] keep private


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Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Erik Josefsson]

Hi Andy, thanks for taking time and for your advise!

On 6/22/19 10:22 PM, Andy Smith wrote:

Hi Erik,

On Fri, Jun 21, 2019 at 03:02:46PM +0200, Erik Josefsson wrote:

Maybe flashbench cannot tell me anything about that anyway?

Are there other tools?

I'm not familiar with flashbench. I like fio. It's available in
Debian.

I like to do the following tests. Example fio command line follows
for each.

- sequential read speed (MB/sec)

 $ fio --name="seqread" \
   --filename="/mnt/fioscratch" \
   --ioengine=libaio \
   --readwrite=read \
   --direct=1 \
   --numjobs=2 \
   --bs=4k \
   --iodepth=4 \
   --size=1g \
   --runtime=300s \
   --gtod_reduce=1 \
   --group_reporting | tee -a /home/$USER/fio.txt

- sequential write speed (MB/sec)

 $ fio --name="seqwrite" \
   --filename="/mnt/fioscratch" \
   --ioengine=libaio \
   --readwrite=write \
   --direct=1 \
   --numjobs=2 \
   --bs=4k \
   --iodepth=4 \
   --size=1g \
   --runtime=300s \
   --gtod_reduce=1 \
   --group_reporting | tee -a /home/$USER/fio.txt

- random 4KiB reads (IOPS)

 $ fio --name="randread" \
   --filename="/mnt/fioscratch" \
   --ioengine=libaio \
   --readwrite=randread \
   --direct=1 \
   --numjobs=2 \
   --bs=4k \
   --iodepth=4 \
   --size=1g \
   --runtime=300s \
   --gtod_reduce=1 \
   --group_reporting | tee -a /home/$USER/fio.txt

- random 4KiB writes (IOPS)

 $ fio --name="randread" \
   --filename="/mnt/fioscratch" \
   --ioengine=libaio \
   --readwrite=randwrite \
   --direct=1 \
   --numjobs=2 \
   --bs=4k \
   --iodepth=4 \
   --size=1g \
   --runtime=300s \
   --gtod_reduce=1 \
   --group_reporting | tee -a /home/$USER/fio.txt

Explanation:

name: Identifies the block of test output in the results output
   file.

filename: This file will be written out and then read from or
   written to. So your test device needs to be mounted on
   /mnt first.



Teres-I has one MicroSD slot, one HDMI and two USB ports.

Is it meaningful to test the SD cards with an USB-adapter? (the MicroSD 
slot would be occupied by the SD card the machine is running from/on)




  As long as your user has write access there,
   fio does not need to be run as root.

readwrite: Sets the mis of reads and writes and whether they are
sequential or random.

direct: Use direct IO, bypassing Linux's page cache. If you don't
 use this, you'll only be testing Linux's cache which would
 distort results since you're only testing 1GiB of data which
 could well fit entirely within your RAM. Note that many
 storage devices have their own cache, but this probably
 isn't relevant for your case.

numjobs: Spawn two processes each of which will be doing the same
  thing at once.

bs: Use 4KiB sized IOs. If you can benchark your real application
 you may find it uses different-sized IOs, but if you don't know
 then 4KiB is a reasonable start.

iodepth: Each process will issue 4 IOs at once, rather than issuing
  one and then waiting for it to complete.

size/runtime: The tests will read or write 1GiB of data but there is
   also a time limit of 5 minutes and if that runs out
   first then the test will stop. I don't think you need
   to do many hours of testing here. After 5 minutes I
   should think the card will be showing its reasonable
   performance.

gtod_reduce: Don't do some tests that require the gettimeofday
  system call. Without this, fio can spend a lot of its
  CPU time calling that system call instead of
  benchmarking, and you rarely require the info it gives
  back anyway. Run without this option once to see if you
  really require it.

group_reporting: Aggregate results from all jobs (processes) within
  the test.

| tee -a …: Output the results both to the screen and append to a
 file in your home directory.

Of those figures, I consider the random ones more important in most
configurations. i.e. if I had to choose between a device that
supported a bit higher sequential read/write but much lower random
read/write, I'd rather have the random read/write, because that
tends to have more impact on interactive usage than sequential.


Yes, going back and forth between Thunderbird and Firefox while copying 
text snippets from one app to the other sometimes ends in a mouse 
pointer freeze.


That's basically what I do most of the time...




SD cards tend to have poor random IO speed so I would never use one
for general purpose computing if I 

Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Andy Smith]

Hi Erik,

On Fri, Jun 21, 2019 at 03:02:46PM +0200, Erik Josefsson wrote:
> Maybe flashbench cannot tell me anything about that anyway?
> 
> Are there other tools?

I'm not familiar with flashbench. I like fio. It's available in
Debian.

I like to do the following tests. Example fio command line follows
for each.

- sequential read speed (MB/sec)

$ fio --name="seqread" \
  --filename="/mnt/fioscratch" \
  --ioengine=libaio \
  --readwrite=read \
  --direct=1 \
  --numjobs=2 \
  --bs=4k \
  --iodepth=4 \
  --size=1g \
  --runtime=300s \
  --gtod_reduce=1 \
  --group_reporting | tee -a /home/$USER/fio.txt

- sequential write speed (MB/sec)

$ fio --name="seqwrite" \
  --filename="/mnt/fioscratch" \
  --ioengine=libaio \
  --readwrite=write \
  --direct=1 \
  --numjobs=2 \
  --bs=4k \
  --iodepth=4 \
  --size=1g \
  --runtime=300s \
  --gtod_reduce=1 \
  --group_reporting | tee -a /home/$USER/fio.txt

- random 4KiB reads (IOPS)

$ fio --name="randread" \
  --filename="/mnt/fioscratch" \
  --ioengine=libaio \
  --readwrite=randread \
  --direct=1 \
  --numjobs=2 \
  --bs=4k \
  --iodepth=4 \
  --size=1g \
  --runtime=300s \
  --gtod_reduce=1 \
  --group_reporting | tee -a /home/$USER/fio.txt

- random 4KiB writes (IOPS)

$ fio --name="randread" \
  --filename="/mnt/fioscratch" \
  --ioengine=libaio \
  --readwrite=randwrite \
  --direct=1 \
  --numjobs=2 \
  --bs=4k \
  --iodepth=4 \
  --size=1g \
  --runtime=300s \
  --gtod_reduce=1 \
  --group_reporting | tee -a /home/$USER/fio.txt

Explanation:

name: Identifies the block of test output in the results output
  file.

filename: This file will be written out and then read from or
  written to. So your test device needs to be mounted on
  /mnt first. As long as your user has write access there,
  fio does not need to be run as root.

readwrite: Sets the mis of reads and writes and whether they are
   sequential or random.

direct: Use direct IO, bypassing Linux's page cache. If you don't
use this, you'll only be testing Linux's cache which would
distort results since you're only testing 1GiB of data which
could well fit entirely within your RAM. Note that many
storage devices have their own cache, but this probably
isn't relevant for your case.

numjobs: Spawn two processes each of which will be doing the same
 thing at once.

bs: Use 4KiB sized IOs. If you can benchark your real application
you may find it uses different-sized IOs, but if you don't know
then 4KiB is a reasonable start.

iodepth: Each process will issue 4 IOs at once, rather than issuing
 one and then waiting for it to complete.

size/runtime: The tests will read or write 1GiB of data but there is
  also a time limit of 5 minutes and if that runs out
  first then the test will stop. I don't think you need
  to do many hours of testing here. After 5 minutes I
  should think the card will be showing its reasonable
  performance.

gtod_reduce: Don't do some tests that require the gettimeofday
 system call. Without this, fio can spend a lot of its
 CPU time calling that system call instead of
 benchmarking, and you rarely require the info it gives
 back anyway. Run without this option once to see if you
 really require it.

group_reporting: Aggregate results from all jobs (processes) within
 the test.

| tee -a …: Output the results both to the screen and append to a
file in your home directory.

Of those figures, I consider the random ones more important in most
configurations. i.e. if I had to choose between a device that
supported a bit higher sequential read/write but much lower random
read/write, I'd rather have the random read/write, because that
tends to have more impact on interactive usage than sequential.

SD cards tend to have poor random IO speed so I would never use one
for general purpose computing if I could use an HDD or SSD instead.

To give you some idea of what decent SSDs manage:


http://strugglers.net/~andy/blog/2019/05/29/linux-raid-10-may-not-always-be-the-best-performer-but-i-dont-know-why/

Cheers,
Andy

-- 
https://bitfolk.com/ -- No-nonsense VPS hosting

Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Erik Josefsson]

Hi David, time is my main constraint. I'm soon going to have none left for 
evaluating benchmarks. I think a better use of available time would be to start 
fundraising to get Teres-I boot without micro SD. But then I don't know if the 
ethical case for that laptop is strong enough compared to other pressing needs 
of the community. My use case seems minimal and/or unrealistic. Best regards. 
//Erik

On 22 June 2019 01:00:51 CEST, David Christensen  
wrote:
>On 6/21/19 12:28 AM, Erik Josefsson wrote:
>> Hi David,
>> 
>> On 6/19/19 3:38 AM, David Christensen wrote:
>>>
>>> The best way to answer your question regarding performance of a size
>N 
>>> SD card vs. a size 2*N SD card is to buy two cards and benchmark
>them 
>>> using your workload.  Please publish your findings.
>> 
>> Please find my four (4) findings below or at 
>> http://paste.debian.net/1088723
>> 
>> The only benchmark I know how to use is flashbench. But unfortunately
>I 
>> don't know how to interpret the resulting data.
>> 
>> I would be immensely grateful for advise on which of the 4 cards to
>use.
>> 
>> The testing was simple. I have downloaded and put the same copy of
>the 
>> redpill RC3 image from http://box.redpill.dk/nonfree/ onto each SD
>card, 
>> then I have followed the instructions. Each card now has an "Extended
>
>> system" created by the command box-add-gui on the same machine.
>> 
>> Then I have installed aptitude, run update and upgrade and autoclean,
>
>> and then installed and run flashbench with parameters: flashbench -a 
>> /dev/mmcblk0 --blocksize=1024
>> 
>> The four cards are:
>> 
>> MicroSD SanDisk Extreme PRO  64GB  [3]  XC II
>> MicroSD SanDisk Extreme PLUS  64GB  [3]  XC I  V30  A2
>> MicroSD SanDisk Extreme PLUS  32GB  [3]  HC I  V30  A1
>> MicroSD SanDisk Ultra  32GB  [1]  HC I  (10)  A1
>> 
>> I can send a picture of the cards off list if this is unclear.
>> 
>> So the question is, which card should I use for Teres-I ?
>> 
>> If there are further benchmarks or tests that could help determine
>which 
>> SD card is the best, I'd be happy to run them.
>> 
>> Best regards.
>> 
>> //Erik
>
>
>I'm not familiar with flashbench.  Every tool has a learning curve;
>it's 
>up to you to decide how much effort you want to put into it.
>
>
>When I wrote "benchmark them using your workload", I was thinking 
>"install Debian, install your apps, run your apps, quantify what you 
>can".  If you're doing command-line stuff, the 'time' built-in for Bash
>
>can be very useful.  But, it's also good to get a subjective feel for 
>the system on the various media -- does it lag?  Does it stutter/ 
>freeze?  Does it crash?
>
>
>I found that Debian and FreeBSD on SanDisk Ultra Fit 16 GB USB 3.0
>flash 
>drives was "good enough" for headless servers, but stuttered/ froze for
>
>interactive graphical desktop use (during disk I/O; especially writes).
>
>I have since migrated to used 16 GB SSD's.  (Does your target hardware 
>have a SATA port?)
>
>
>David

-- 
Sent from my Android device with K-9 Mail. Please excuse my brevity.

Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[David Christensen]

On 6/21/19 12:28 AM, Erik Josefsson wrote:

Hi David,

On 6/19/19 3:38 AM, David Christensen wrote:


The best way to answer your question regarding performance of a size N 
SD card vs. a size 2*N SD card is to buy two cards and benchmark them 
using your workload.  Please publish your findings.


Please find my four (4) findings below or at 
http://paste.debian.net/1088723


The only benchmark I know how to use is flashbench. But unfortunately I 
don't know how to interpret the resulting data.


I would be immensely grateful for advise on which of the 4 cards to use.

The testing was simple. I have downloaded and put the same copy of the 
redpill RC3 image from http://box.redpill.dk/nonfree/ onto each SD card, 
then I have followed the instructions. Each card now has an "Extended 
system" created by the command box-add-gui on the same machine.


Then I have installed aptitude, run update and upgrade and autoclean, 
and then installed and run flashbench with parameters: flashbench -a 
/dev/mmcblk0 --blocksize=1024


The four cards are:

MicroSD SanDisk Extreme PRO  64GB  [3]  XC II
MicroSD SanDisk Extreme PLUS  64GB  [3]  XC I  V30  A2
MicroSD SanDisk Extreme PLUS  32GB  [3]  HC I  V30  A1
MicroSD SanDisk Ultra  32GB  [1]  HC I  (10)  A1

I can send a picture of the cards off list if this is unclear.

So the question is, which card should I use for Teres-I ?

If there are further benchmarks or tests that could help determine which 
SD card is the best, I'd be happy to run them.


Best regards.

//Erik



I'm not familiar with flashbench.  Every tool has a learning curve; it's 
up to you to decide how much effort you want to put into it.



When I wrote "benchmark them using your workload", I was thinking 
"install Debian, install your apps, run your apps, quantify what you 
can".  If you're doing command-line stuff, the 'time' built-in for Bash 
can be very useful.  But, it's also good to get a subjective feel for 
the system on the various media -- does it lag?  Does it stutter/ 
freeze?  Does it crash?



I found that Debian and FreeBSD on SanDisk Ultra Fit 16 GB USB 3.0 flash 
drives was "good enough" for headless servers, but stuttered/ froze for 
interactive graphical desktop use (during disk I/O; especially writes). 
I have since migrated to used 16 GB SSD's.  (Does your target hardware 
have a SATA port?)



David

Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Erik Josefsson]

On 6/21/19 12:17 PM, Jonas Smedegaard wrote:

Quoting Erik Josefsson (2019-06-21 09:28:38)

On 6/19/19 3:38 AM, David Christensen wrote:

The best way to answer your question regarding performance of a size
N SD card vs. a size 2*N SD card is to buy two cards and benchmark
them using your workload.  Please publish your findings.

Please find my four (4) findings below or at
http://paste.debian.net/1088723

The only benchmark I know how to use is flashbench. But unfortunately
I don't know how to interpret the resulting data.

flashbench is for benchmarking page/erase-blocks/allocation-group (not
transfer speed).

My tool to generate images supports custom-aligned since April 28:
https://salsa.debian.org/tinker-team/box/commit/be07a3a1b0-I


That's great, but granted all 4 cards are optimized by your scripts, the 
question is if flashbench can tell me which one to pick?


All of them work fine, but I want to spend time with the one that is 
best for "my workload", as suggested by David Christensen earlier in the 
thread.


Maybe flashbench cannot tell me anything about that anyway?

Are there other tools?

//Erik

Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Jonas Smedegaard]

Quoting Erik Josefsson (2019-06-21 09:28:38)
> On 6/19/19 3:38 AM, David Christensen wrote:
>> The best way to answer your question regarding performance of a size 
>> N SD card vs. a size 2*N SD card is to buy two cards and benchmark 
>> them using your workload.  Please publish your findings.
>
> Please find my four (4) findings below or at 
> http://paste.debian.net/1088723
>
> The only benchmark I know how to use is flashbench. But unfortunately 
> I don't know how to interpret the resulting data.

flashbench is for benchmarking page/erase-blocks/allocation-group (not 
transfer speed).

My tool to generate images supports custom-aligned since April 28: 
https://salsa.debian.org/tinker-team/box/commit/be07a3a1b0

Above git commit includes links to some notes on the topic:

https://wiki.gentoo.org/wiki/SDCard#Solution_2:_Tuned_ext4
https://thelastmaimou.wordpress.com/2013/05/04/magic-soup-ext4-with-ssd-stripes-and-strides/
https://lists.linaro.org/pipermail/flashbench-results/2014-July/000479.html


 - Jonas

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Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Erik Josefsson]

Hi David,

On 6/19/19 3:38 AM, David Christensen wrote:


The best way to answer your question regarding performance of a size N 
SD card vs. a size 2*N SD card is to buy two cards and benchmark them 
using your workload.  Please publish your findings.


Please find my four (4) findings below or at 
http://paste.debian.net/1088723


The only benchmark I know how to use is flashbench. But unfortunately I 
don't know how to interpret the resulting data.


I would be immensely grateful for advise on which of the 4 cards to use.

The testing was simple. I have downloaded and put the same copy of the 
redpill RC3 image from http://box.redpill.dk/nonfree/ onto each SD card, 
then I have followed the instructions. Each card now has an "Extended 
system" created by the command box-add-gui on the same machine.


Then I have installed aptitude, run update and upgrade and autoclean, 
and then installed and run flashbench with parameters: flashbench -a 
/dev/mmcblk0 --blocksize=1024


The four cards are:

MicroSD SanDisk Extreme PRO  64GB  [3]  XC II
MicroSD SanDisk Extreme PLUS  64GB  [3]  XC I  V30  A2
MicroSD SanDisk Extreme PLUS  32GB  [3]  HC I  V30  A1
MicroSD SanDisk Ultra  32GB  [1]  HC I  (10)  A1

I can send a picture of the cards off list if this is unclear.

So the question is, which card should I use for Teres-I ?

If there are further benchmarks or tests that could help determine which 
SD card is the best, I'd be happy to run them.


Best regards.

//Erik

MicroSD SanDisk Extreme PRO  64GB  [3]  XC II
debian@box:~$ sudo flashbench -a /dev/mmcblk0 --blocksize=1024
align 17179869184   pre 515µs   on 809µspost 452µs  diff 
325µs
align 8589934592pre 515µs   on 736µspost 427µs  diff 
265µs
align 4294967296pre 537µs   on 823µspost 460µs  diff 
325µs
align 2147483648pre 545µs   on 893µspost 471µs  diff 
385µs
align 1073741824pre 517µs   on 749µspost 434µs  diff 
274µs
align 536870912 pre 526µs   on 763µspost 445µs  diff 277µs
align 268435456 pre 527µs   on 769µspost 448µs  diff 282µs
align 134217728 pre 540µs   on 820µspost 446µs  diff 327µs
align 67108864  pre 514µs   on 754µspost 449µs  diff 273µs
align 33554432  pre 506µs   on 722µspost 417µs  diff 261µs
align 16777216  pre 539µs   on 660µspost 460µs  diff 160µs
align 8388608   pre 539µs   on 670µspost 458µs  diff 171µs
align 4194304   pre 541µs   on 669µspost 466µs  diff 165µs
align 2097152   pre 547µs   on 649µspost 463µs  diff 144µs
align 1048576   pre 544µs   on 639µspost 458µs  diff 138µs
align 524288pre 545µs   on 658µspost 460µs  diff 155µs
align 262144pre 545µs   on 655µspost 460µs  diff 152µs
align 131072pre 540µs   on 620µspost 455µs  diff 122µs
align 65536 pre 541µs   on 624µspost 458µs  diff 125µs
align 32768 pre 538µs   on 622µspost 461µs  diff 122µs
align 16384 pre 478µs   on 633µspost 457µs  diff 165µs
align 8192  pre 501µs   on 516µspost 480µs  diff 25.7µs
align 4096  pre 509µs   on 528µspost 465µs  diff 41.2µs
align 2048  pre 514µs   on 538µspost 508µs  diff 27.6µs


MicroSD SanDisk Extreme PLUS  64GB  [3]  XC I  V30  A2
debian@box:~$ sudo flashbench -a /dev/mmcblk0 --blocksize=1024
align 17179869184   pre 567µs   on 603µspost 494µs  diff 
72.6µs
align 8589934592pre 557µs   on 583µspost 442µs  diff 
83.9µs
align 4294967296pre 689µs   on 784µspost 564µs  diff 
157µs
align 2147483648pre 654µs   on 726µspost 593µs  diff 
103µs
align 1073741824pre 579µs   on 638µspost 522µs  diff 
87.7µs
align 536870912 pre 570µs   on 652µspost 529µs  diff 102µs
align 268435456 pre 524µs   on 564µspost 500µs  diff 52.5µs
align 134217728 pre 654µs   on 730µspost 616µs  diff 95.3µs
align 67108864  pre 664µs   on 728µspost 600µs  diff 96.3µs
align 33554432  pre 576µs   on 637µspost 530µs  diff 84.1µs
align 16777216  pre 628µs   on 694µspost 568µs  diff 95.9µs
align 8388608   pre 594µs   on 654µspost 567µs  diff 73.6µs
align 4194304   pre 628µs   on 680µspost 580µs  diff 76µs
align 2097152   pre 576µs   on 602µspost 562µs  diff 33.5µs
align 1048576   pre 578µs   on 577µspost 572µs  diff 2.21µs
align 524288pre 585µs   on 585µspost 578µs  diff 3.55µs
align 262144pre 587µs   on 592µspost 584µs  diff 6.52µs
align 131072pre 616µs   on 636µspost 613µs  diff 21.4µs
align 65536 pre 594µs

Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Jonas Smedegaard]

Quoting Erik Josefsson (2019-06-20 08:58:34)
> On 6/19/19 2:04 PM, Jonas Smedegaard wrote:
> >> Or, a better question, is it within reach to run a Debian Pure 
> >> Blend on Teres-I without an external SD card? If so, is Dan Ritter 
> >> right that it will be 2x to 8x faster?
> > Yes, it certainly is within reach, just needs someone to do the 
> > reaching.
> >
> > This seems a good starting point for such adventure: 
> > https://github.com/armbian/build/blob/master/packages/bsp/common/usr/sbin/nand-sata-install
> >
> Very good!
> 
> Indeed, one of the comments to the code on that page says ""In case of 
> eMMC it's also possible to transfer the bootloader to eMMC in a single 
> step so from then on running without SD card is possible.".
> 
> Somehow the Olimex folks managed to make Teres-I run Ubuntu without SD 
> card.
> 
> Grateful for advice who to talk to!

The authors of above script: https://forum.armbian.com/

Board makers: https://www.olimex.com/wiki/GTC-FAQ

SoC developers: https://linux-sunxi.org/Category:Community

Happy hacking!


 - Jonas

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Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Erik Josefsson]

On 6/19/19 2:04 PM, Jonas Smedegaard wrote:

Or, a better question, is it within reach to run a Debian Pure Blend
on Teres-I without an external SD card? If so, is Dan Ritter right
that it will be 2x to 8x faster?

Yes, it certainly is within reach, just needs someone to do the
reaching.

This seems a good starting point for such adventure:
https://github.com/armbian/build/blob/master/packages/bsp/common/usr/sbin/nand-sata-install


Very good!

Indeed, one of the comments to the code on that page says ""In case of 
eMMC it's also possible to transfer the bootloader to eMMC in a single 
step so from then on running without SD card is possible.".


Somehow the Olimex folks managed to make Teres-I run Ubuntu without SD card.

Grateful for advice who to talk to!

Best regards.

//Erik

Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[David Christensen]

On 6/19/19 3:40 AM, deloptes wrote:

David Christensen wrote:

I have tried running machines without swap, but found that they crashed.
Now I always include a 1 GB swap partition when installing.


why not using swap (if disk space is available) disk space is cheap.


I built systems on USB flash drives without swap to reduce wear on the 
USB flash drive and to see if they worked.



David

Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Dan Ritter]

Erik Josefsson wrote: 
> Hi Dan,
> 
> On 6/18/19 11:57 PM, Dan Ritter wrote:
> > Nicholas Geovanis wrote:
> > > On Tue, Jun 18, 2019, 4:10 PM Erik Josefsson <
> > > erik.hjalmar.josefs...@gmail.com> wrote:
> > > 
> > > > The Ubuntu version that Teres-I comes with feels almost as good, which 
> > > > is
> > > > why I still don't understand why running Debian from the SD-card 
> > > > doesn't.
> > > > 
> > > Then I would be interested to know which release of Ubuntu and see an
> > > installed package list. But i will hit the websites, no need to post here.
> > He seems to be comparing speed of Ubuntu on an internal eMMC
> > storage (16GB, 8 bit interface) to the speed of Debian on an
> > SD card interface (either 4 bit or 1 bit interface, depending
> > on what they chose).
> > 
> > The eMMC should transfer twice as fast at minimum, and possibly
> > 8x as fast as the SD card.
> 
> I obviously didn't get that memo.
> 
> > -dsr- (I looked at the spec.)
> > 
> You don't happen to see in the spec. which boot key to press to get Teres-I
> to start a netinstall from USB?

Sorry, I was looking at the hardware spec. I don't see any info
on boot sequences.

-dsr-

Example of an M2 form factor SSD (was: Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[rhkramer]

On Tuesday, June 18, 2019 10:06:41 AM rhkra...@gmail.com wrote:
> About the only thing I'd add to what others have said is that they now make
> SSDs in a different form factor -- if you look for them, they start with an
> M, iirc -- they are in the same size range as an SD card (well, a regular
> one, not a micro).
> 
> You need a special socket to plug them into, and I'm not sure which (if
> any) single board computers (I'm trying to use that to refer to computers
> using a system on a chip) have that kind of socket.

Here is a link to an M2 form factor SSD (and some details from the 
description):  (The example is a Samsung, and I found the example at Newegg, 
but this should not be considered an endorsement or advertising for either of 
them.)

By the way, the dimensions of these units vary, and the dimensions are encoded 
in the form factor, for example, the example M2 2280 device is 22 mm  wide by 
80 mm long (about 1" x 3").  (And 2.38 mm (~0.1 inch) thick, but, as far as I 
know, the 2 in the M2 does not designate thickness -- I could be  wrong.)


SAMSUNG 970 EVO PLUS M.2 2280 250GB PCIe Gen 3.0 x4, NVMe 1.3 V-NAND 3-bit MLC 
Internal Solid State Drive (SSD) MZ-V7S250B/AM 

https://www.newegg.com/samsung-970-evo-
plus-250gb/p/N82E16820147741?Item=N82E16820147741_medium=Email_source=GD061919_mmc=EMC-
GD061919-_-landing-_-Item-_-20-147-741

...

Form Factor
M.2 2280
Capacity
250GB
...

Dimensions & Weight

Height
2.38mm

Width
22.15mm

Depth
80.15mm

Weight
8.00g

Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Jonas Smedegaard]

Quoting Erik Josefsson (2019-06-19 13:38:32)
> On 6/19/19 1:15 PM, Jonas Smedegaard wrote:
> 
> > Quoting deloptes (2019-06-19 12:42:13)
> >> Jonas Smedegaard wrote:
> >>
> >>> In short, you really_really_ want netinstall from MicroSD!
> >> What about debootstrap? IS it possible to use it for that SoC?
> > Certainly.  Debian-installer uses debootstrap internally so that is 
> > a must.  The images Erik has used until now -http://box.redpill.dk/ 
> > - are also built with debootstrap (or rather the more flexible 
> > multistrap) using the framework I referenced in my previous post: 
> > https://salsa.debian.org/tinker-team/box
> >
> > My point in above quote is which_medium_ you want to boot from 
> > initially on a Teres-I: MicroSD rather than USB (not which method of 
> > installation you want).
> >
> > My work specifically explores how to avoid the tedious process of 
> > running debian-installer on the relatively slow Teres-I but 
> > reach_same_ result as if doing so - because in my experience running 
> > debootstrap directly can easily lead to a slightly broken system.
> 
> It is quite possible that my impression that the Ubuntu instance that 
> Teres-I is shipped with is significantly faster than your redpills is 
> just imaginary, but then Dan Ritter seemed to confirm that that 
> "native Ubuntu" probably is 2x to 8x faster.
> 
> If "native Ubuntu" is faster than "SD redpill", then I wonder how the 
> Olimex people got their Ubuntu installed in the first place? They 
> couldn't have used the Debian Installer, could they?
> 
> Or, a better question, is it within reach to run a Debian Pure Blend 
> on Teres-I without an external SD card? If so, is Dan Ritter right 
> that it will be 2x to 8x faster?

Yes, it certainly is within reach, just needs someone to do the 
reaching.

This seems a good starting point for such adventure: 
https://github.com/armbian/build/blob/master/packages/bsp/common/usr/sbin/nand-sata-install


 - Jonas

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Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Erik Josefsson]

On 6/19/19 1:15 PM, Jonas Smedegaard wrote:


Quoting deloptes (2019-06-19 12:42:13)

Jonas Smedegaard wrote:


In short, you really_really_  want netinstall from MicroSD!

What about debootstrap? IS it possible to use it for that SoC?

Certainly.  Debian-installer uses debootstrap internally so that is a
must.  The images Erik has used until now -http://box.redpill.dk/  - are
also built with debootstrap (or rather the more flexible multistrap)
using the framework I referenced in my previous post:
https://salsa.debian.org/tinker-team/box

My point in above quote is which_medium_  you want to boot from
initially on a Teres-I: MicroSD rather than USB (not which method of
installation you want).

My work specifically explores how to avoid the tedious process of
running debian-installer on the relatively slow Teres-I but reach_same_  
result as if doing so - because in my experience running debootstrap

directly can easily lead to a slightly broken system.


It is quite possible that my impression that the Ubuntu instance that 
Teres-I is shipped with is significantly faster than your redpills is 
just imaginary, but then Dan Ritter seemed to confirm that that "native 
Ubuntu" probably is 2x to 8x faster.


If "native Ubuntu" is faster than "SD redpill", then I wonder how the 
Olimex people got their Ubuntu installed in the first place? They 
couldn't have used the Debian Installer, could they?


Or, a better question, is it within reach to run a Debian Pure Blend on 
Teres-I without an external SD card? If so, is Dan Ritter right that it 
will be 2x to 8x faster?


//Erik

Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Jonas Smedegaard]

Quoting deloptes (2019-06-19 12:42:13)
> Jonas Smedegaard wrote:
> 
> > In short, you really _really_ want netinstall from MicroSD!
> 
> What about debootstrap? IS it possible to use it for that SoC?

Certainly.  Debian-installer uses debootstrap internally so that is a 
must.  The images Erik has used until now - http://box.redpill.dk/ - are 
also built with debootstrap (or rather the more flexible multistrap) 
using the framework I referenced in my previous post: 
https://salsa.debian.org/tinker-team/box

My point in above quote is which _medium_ you want to boot from 
initially on a Teres-I: MicroSD rather than USB (not which method of 
installation you want).

My work specifically explores how to avoid the tedious process of 
running debian-installer on the relatively slow Teres-I but reach _same_ 
result as if doing so - because in my experience running debootstrap 
directly can easily lead to a slightly broken system.


 - Jonas

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Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[deloptes]

Jonas Smedegaard wrote:

> In short, you really _really_ want netinstall from MicroSD!

What about debootstrap? IS it possible to use it for that SoC?

Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[deloptes]

David Christensen wrote:

> I have considered installing and running Debian on SD cards.  At this
> point, I would probably choose a "high endurance" device rather than a
> "fast' device, because I want the system to last.  (The few solid-state
> device failures I have seen all followed the same pattern:  working to
> non-working, with no warning and little or no recovery.  At least one
> included the smell of roasting electronics; e.g. "let the smoke out".)
> 

CF cards are much better but also more expensive. 
No electronic device is meant to work forever - disaster recovery should be
always considered.

Depends on how your setup looks like, typically Debian is <4GB. I have
installations from 450MB to 2GB.

> 
> I have tried running machines without swap, but found that they crashed.
> Now I always include a 1 GB swap partition when installing.

why not using swap (if disk space is available) disk space is cheap.

regards

Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Jonas Smedegaard]

Quoting Erik Josefsson (2019-06-19 11:53:51)
> You don't happen to see in the spec. which boot key to press to get 
> Teres-I to start a netinstall from USB?

Whereas boot from USB is (nowadays, wasn't always) comon among 
IBM-compatible PCs, that is not common among ARM devices, and it is not 
supported on Allwinner A64 SoC used in (current release of) Teres-I.

Here is the technical details: https://linux-sunxi.org/BROM#A64

...or more accurately an USB-based "FEL" mode exists but is... complex. 
If you really want to try that route (not recommended!) then see also 
https://linux-sunxi.org/FEL and if not yet scared off check how to 
enable it at https://linux-sunxi.org/Olimex_Teres-A64#FEL_mode

In short, you really _really_ want netinstall from MicroSD!


> The new Debian-Installer worked perfectly fine with an old HP 
> workstation a couple of weeks ago.
> 
> https://www.debian.org/devel/debian-installer/
> 
> I'd love to try it on Teres-I.

Teres-I is not yet supported by debian-installer yet - the closest 
approximation I know of is achieved using my build framework.  It's been 
a while since I tested the netinstall image builds myself (as you know I 
have been super busy refining the the prebuilt images that you have been 
using) but it should be something like this:

  git clone https://salsa.debian.org/tinker-team/box
  make images/d-i/core_teres1-teres1-buster.img.gz


 - Jonas

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Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Erik Josefsson]

Hi Dan,

On 6/18/19 11:57 PM, Dan Ritter wrote:

Nicholas Geovanis wrote:

On Tue, Jun 18, 2019, 4:10 PM Erik Josefsson <
erik.hjalmar.josefs...@gmail.com> wrote:


The Ubuntu version that Teres-I comes with feels almost as good, which is
why I still don't understand why running Debian from the SD-card doesn't.


Then I would be interested to know which release of Ubuntu and see an
installed package list. But i will hit the websites, no need to post here.

He seems to be comparing speed of Ubuntu on an internal eMMC
storage (16GB, 8 bit interface) to the speed of Debian on an
SD card interface (either 4 bit or 1 bit interface, depending
on what they chose).

The eMMC should transfer twice as fast at minimum, and possibly
8x as fast as the SD card.


I obviously didn't get that memo.


-dsr- (I looked at the spec.)

You don't happen to see in the spec. which boot key to press to get 
Teres-I to start a netinstall from USB?


The new Debian-Installer worked perfectly fine with an old HP 
workstation a couple of weeks ago.


https://www.debian.org/devel/debian-installer/

I'd love to try it on Teres-I.

Thanks a million!

//Erik

Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Jonas Smedegaard]

Quoting David Christensen (2019-06-19 03:38:56)
> On 6/18/19 5:26 AM, Erik Josefsson wrote: If the Teres-I is a "Do It 
> Yourself Open Source Hardware and Software Hacker's friendly Modular 
> Laptop", where are the downloads?
> 
>  https://www.olimex.com/Products/DIY-Laptop/

Olimex Armbian-based downloads are documented 2 levels deeper (follow 
"Kits" in the menu): 
https://www.olimex.com/Products/DIY-Laptop/KITS/TERES-A64-BLACK/open-source-hardware
 
https://www.olimex.com/Products/DIY-Laptop/KITS/TERES-A64-WHITE/open-source-hardware

My alternative Debian-based images are at http://box.redpill.dk/


 - Jonas

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Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[David Christensen]

On 6/18/19 5:26 AM, Erik Josefsson wrote:
This is another quite open question that I probably could research 
myself, if I had the time.


As far as I understand, it is quite recent that SD cards are fast and 
large enough to be able to carry and run an entire Debian instance.


If this is the case, maybe there is only theory available regarding 
whether you can make a computer "run faster" on a 64GB SD card than on a 
32GB SD card when cards are otherwise identical.


I don't really know how swap works on a standard computer, even less how 
it works when the whole computer runs from/on a SD card.


Swap is supposed to be make your computer pretend that you have more RAM 
than it actually has, but if the whole computer is running from/on RAM 
(or is it?), then what does swap mean?


On Teres-I with redpill RC2 (now there is a RC3 that I have not yet 
installed) an unfortunate website with pop up commercials (like dn.se) 
can eat all performance there is and freeze the mouse for hours. I would 
guess that could have been fixed on a normal computer with "more RAM", 
i.e., "more swap"? But is the same true for e.g. Teres-I?



Second question is if it is meaningful to buy a "super duper blazing 
fast" SD card for the task to run a whole Debian system?


There is a very expensive 64GB SD card from SanDisk that is called 
Extreme Pro that costs twice as much as same size Extreme Plus. Specs 
say it is "super duper blazing fast" for video in "Ultra HD 4K", but 
would Pro also be faster than Plus for the task of running Thunderbird 
and Firefox at the same time?



Best regards.

//Erik



The best way to answer your question regarding performance of a size N 
SD card vs. a size 2*N SD card is to buy two cards and benchmark them 
using your workload.  Please publish your findings.



I have considered installing and running Debian on SD cards.  At this 
point, I would probably choose a "high endurance" device rather than a 
"fast' device, because I want the system to last.  (The few solid-state 
device failures I have seen all followed the same pattern:  working to 
non-working, with no warning and little or no recovery.  At least one 
included the smell of roasting electronics; e.g. "let the smoke out".)



I have tried running machines without swap, but found that they crashed. 
 Now I always include a 1 GB swap partition when installing.



I have run Debian on USB flash drives 24x7 in headless servers and in 
desktops, but cheap used SSD's are better.  (That said, a USB flash 
drive install is invaluable for trouble-shooting and maintenance.)



"Run from RAM" means "Live CD".  I created my own Debian-based live CD 
in the past.  I believe the starting point was here:


https://wiki.debian.org/DebianLive


If the Teres-I is a "Do It Yourself Open Source Hardware and Software 
Hacker's friendly Modular Laptop", where are the downloads?


https://www.olimex.com/Products/DIY-Laptop/


David

Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Jonas Smedegaard]

Quoting Erik Josefsson (2019-06-18 23:10:03)
> Because PureOS is a Debian Pure Blend, isn't it?

No, PureOS is Debian Blend (one of my main tasks in the company is to 
work on that) but not a Pure Blend: It contains non-Debian parts and 
will likely always due to a core aim of complying with both Debian and 
FSF principles so as long as Debian and FSF disagrees on some marginal 
details PureOS will stay a "non-pure" Debian Blend: 
https://wiki.debian.org/DebianPureBlends#Terminology


 - Jonas

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Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Dan Ritter]

Nicholas Geovanis wrote: 
> On Tue, Jun 18, 2019, 4:10 PM Erik Josefsson <
> erik.hjalmar.josefs...@gmail.com> wrote:
> 
> > The Ubuntu version that Teres-I comes with feels almost as good, which is
> > why I still don't understand why running Debian from the SD-card doesn't.
> >
> Then I would be interested to know which release of Ubuntu and see an
> installed package list. But i will hit the websites, no need to post here.

He seems to be comparing speed of Ubuntu on an internal eMMC
storage (16GB, 8 bit interface) to the speed of Debian on an
SD card interface (either 4 bit or 1 bit interface, depending 
on what they chose).

The eMMC should transfer twice as fast at minimum, and possibly
8x as fast as the SD card.

-dsr- (I looked at the spec.)

Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Nicholas Geovanis]

On Tue, Jun 18, 2019, 4:10 PM Erik Josefsson <
erik.hjalmar.josefs...@gmail.com> wrote:

> The Ubuntu version that Teres-I comes with feels almost as good, which is
> why I still don't understand why running Debian from the SD-card doesn't.
>
Then I would be interested to know which release of Ubuntu and see an
installed package list. But i will hit the websites, no need to post here.

>
> //Erik
>

Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Erik Josefsson]

On 6/18/19 9:04 PM, Jonas Smedegaard wrote:

I need either to drop gui or figure out a way to make the Teres-I
laptop perform almost as good as a Lenovo N22-20 Chromebook model 80SF
(which is what the kids had last year).

Such a Lenovo Chromebook outperforms the Teres-1 on every way.


I know, that's why I wrote "almost as good".

The Ubuntu version that Teres-I comes with feels almost as good, which 
is why I still don't understand why running Debian from the SD-card doesn't.


Maybe it's just a technical fact that it can never do, regardless of 
optimizations and settings, and that I didn't get that memo?



You should use Teres-I not for its speed but its price and ethics:
https://www.olimex.com/Products/DIY-Laptop/


The real world cost of using Teres-I with a Pure Blend can only be 
justified with the latter.


The only other, in that sense, ethical laptop I know of are the ones you 
can buy from puri.sm.


Because PureOS is a Debian Pure Blend, isn't it?

//Erik

Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Jochen Spieker]

Erik Josefsson:
> 
> As far as I understand, it is quite recent that SD cards are fast and large
> enough to be able to carry and run an entire Debian instance.

The capacity is not a problem for quite some time, depending on your
space requirements. You can still run a minimal Debian on way less than
1GB. The same is true for the speed. SD cards tend to be used with and
optimized for large(ish) files like photos and videos. Reading and
writing these files should be quite fast, but I would not expect great
performance for random I/O on small files.

> If this is the case, maybe there is only theory available regarding whether
> you can make a computer "run faster" on a 64GB SD card than on a 32GB SD
> card when cards are otherwise identical.

I don't know.

> I don't really know how swap works on a standard computer, even less how it
> works when the whole computer runs from/on a SD card.

The same as with other storage. Swap means using persistent, slow and
cheap storage as RAM. It is exactly that, cheap and painfully slow.
Under normal circumstances you should avoid swapping like the plague.
(Yes, the Linux kernel tends to make use of swap in the background "just
in case". It does not need necessarily to worry you if free(1) or top(1)
report swap usage.)

> Swap is supposed to be make your computer pretend that you have more RAM
> than it actually has, but if the whole computer is running from/on RAM (or
> is it?), then what does swap mean?

What do you mean, running from RAM? I do not see a connection of this
sentence with your previous questions about SD cards. In any case,
swapping to SD card may be even worse than swapping to traditional hard
disks.

> On Teres-I with redpill RC2 (now there is a RC3 that I have not yet
> installed) an unfortunate website with pop up commercials (like dn.se) can
> eat all performance there is and freeze the mouse for hours. I would guess
> that could have been fixed on a normal computer with "more RAM", i.e., "more
> swap"? But is the same true for e.g. Teres-I?

I don't know that hardware except for what I was able to google quickly.
But "more RAM" and "more swap" are very different things. Swap does not
help your computer to perform better. It helps your computer to do
things very, very slowly that it otherwise would not be able to do at
all.

> Second question is if it is meaningful to buy a "super duper blazing fast"
> SD card for the task to run a whole Debian system?
> 
> There is a very expensive 64GB SD card from SanDisk that is called Extreme
> Pro that costs twice as much as same size Extreme Plus. Specs say it is
> "super duper blazing fast" for video in "Ultra HD 4K", but would Pro also be
> faster than Plus for the task of running Thunderbird and Firefox at the same
> time?

Not necessarily. I would try to look for benchmarks that also test
random I/O. Also, it sounds more like your system is memory-constrained
and even the fastest SD cards will not help you with that, see above.

J.
-- 
I think the environment will be okay.
[Agree]   [Disagree]
 


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Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Jonas Smedegaard]

Quoting Erik Josefsson (2019-06-18 18:15:39)
> On 6/18/19 5:46 PM, Nicholas Geovanis wrote:
> >
> > If the computer runs from the SD card, the memory you are 
> > talking about is also on that same SD card, no?
> >
> > No. The SD card is analogous to the hard drive, not to the RAM.
> 
> Thanks! Now things start to make sense again :-)
> 
> That means there could be some margin of performance optimization of 
> Teres-I, but the non-SD-card hardware together with the "IO bus 
> design" songbird mentioned (thank you songbird!) is non-configurable, 
> i.e. the real bottleneck.
> 
> I need either to drop gui or figure out a way to make the Teres-I 
> laptop perform almost as good as a Lenovo N22-20 Chromebook model 80SF 
> (which is what the kids had last year).

Such a Lenovo Chromebook outperforms the Teres-1 on every way.

You should use Teres-I not for its speed but its price and ethics: 
https://www.olimex.com/Products/DIY-Laptop/


 - Jonas

-- 
 * Jonas Smedegaard - idealist & Internet-arkitekt
 * Tlf.: +45 40843136  Website: http://dr.jones.dk/

 [x] quote me freely  [ ] ask before reusing  [ ] keep private


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Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Erik Josefsson]

On 6/18/19 5:46 PM, Nicholas Geovanis wrote:


If the computer runs from the SD card, the memory you are talking
about is also on that same SD card, no?

No. The SD card is analogous to the hard drive, not to the RAM.


Thanks! Now things start to make sense again :-)

That means there could be some margin of performance optimization of 
Teres-I, but the non-SD-card hardware together with the "IO bus design" 
songbird mentioned (thank you songbird!) is non-configurable, i.e. the 
real bottleneck.


I need either to drop gui or figure out a way to make the Teres-I laptop 
perform almost as good as a Lenovo N22-20 Chromebook model 80SF (which 
is what the kids had last year).


Or drop Teres-I.

//Erik

Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Dan Ritter]

rhkra...@gmail.com wrote: 
> On Tuesday, June 18, 2019 11:21:51 AM Erik Josefsson wrote:
> > If the computer runs from the SD card, the memory you are talking about
> > is also on that same SD card, no?
> 
> I should let Andy speak for himself, but, I believe the answer is no -- 
> earlier in the thread something made me think you were confusing RAM with 
> memory on the SD card -- RAM is not on the SD card, it is "closer" to the 
> CPU, 
> on or near the motherboard.  (I don't know whether an SOC (System on a Chip) 
> includes the RAM on the chip -- if not, it is much closer, physically and 
> electrically to the CPU than the SD card.

Some SoCs are literally mounted directly beneath a RAM chip;
some have a fixed amount of RAM built-in; some use an external
RAM supply (which may be soldered or socketed).

The useful ways of generically referring to these things:

memory = RAM, volatile on power loss

storage = "disk" of some variety, retaining information through
  power loss

-dsr-

Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Nicholas Geovanis]

On Tue, Jun 18, 2019 at 10:22 AM Erik Josefsson <
erik.hjalmar.josefs...@gmail.com> wrote:

> If the computer runs from the SD card, the memory you are talking about is
> also on that same SD card, no?
>
No. The SD card is analogous to the hard drive, not to the RAM.

> Thanks again!
>
> //Erik
>

Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[rhkramer]

On Tuesday, June 18, 2019 11:21:51 AM Erik Josefsson wrote:
> Hi Andy, thanks for taking time!
> 
> On 6/18/19 3:14 PM, Andy Smith wrote:
> >> There is a very expensive 64GB SD card from SanDisk that is called
> >> Extreme Pro that costs twice as much as same size Extreme Plus. Specs
> >> say it is "super duper blazing fast" for video in "Ultra HD 4K", but
> >> would Pro also be faster than Plus for the task of running Thunderbird
> >> and Firefox at the same time?
> > 
> > Running big apps like that will benefit more from having enough
> > memory. After that is satisfied, fast storage will certainly help.
> > You'll have to look at the exact specifications of Plus vs Pro.
> 
> Here's probably one of my large white spots, but what do you mean with
> "enough memory"?
> 
> If the computer runs from the SD card, the memory you are talking about
> is also on that same SD card, no?

I should let Andy speak for himself, but, I believe the answer is no -- 
earlier in the thread something made me think you were confusing RAM with 
memory on the SD card -- RAM is not on the SD card, it is "closer" to the CPU, 
on or near the motherboard.  (I don't know whether an SOC (System on a Chip) 
includes the RAM on the chip -- if not, it is much closer, physically and 
electrically to the CPU than the SD card.


> 
> If yes, then optimizing available SD card memory (e.g. 32GB or 64GB)
> would yield different performance results, but that does not seem to be
> the case!
> 
> > What are you trying to achieve?
> 
> I want to make up my mind whether I will have the time to use Teres-I
> with redpill RC3 at work (i.e. in school).
> 
> Thanks again!
> 
> //Erik

Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Erik Josefsson]

Hi Andy, thanks for taking time!

On 6/18/19 3:14 PM, Andy Smith wrote:

There is a very expensive 64GB SD card from SanDisk that is called Extreme
Pro that costs twice as much as same size Extreme Plus. Specs say it is
"super duper blazing fast" for video in "Ultra HD 4K", but would Pro also be
faster than Plus for the task of running Thunderbird and Firefox at the same
time?

Running big apps like that will benefit more from having enough
memory. After that is satisfied, fast storage will certainly help.
You'll have to look at the exact specifications of Plus vs Pro.


Here's probably one of my large white spots, but what do you mean with 
"enough memory"?


If the computer runs from the SD card, the memory you are talking about 
is also on that same SD card, no?


If yes, then optimizing available SD card memory (e.g. 32GB or 64GB) 
would yield different performance results, but that does not seem to be 
the case!




What are you trying to achieve?


I want to make up my mind whether I will have the time to use Teres-I 
with redpill RC3 at work (i.e. in school).


Thanks again!

//Erik

Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[rhkramer]

About the only thing I'd add to what others have said is that they now make 
SSDs in a different form factor -- if you look for them, they start with an M, 
iirc -- they are in the same size range as an SD card (well, a regular one, 
not a micro).  

You need a special socket to plug them into, and I'm not sure which (if any) 
single board computers (I'm trying to use that to refer to computers using a 
system on a chip) have that kind of socket.



On Tuesday, June 18, 2019 09:14:19 AM Andy Smith wrote:
> Hi Erik,
> 
> On Tue, Jun 18, 2019 at 02:26:57PM +0200, Erik Josefsson wrote:
> > As far as I understand, it is quite recent that SD cards are fast and
> > large enough to be able to carry and run an entire Debian instance.
> 
> Not really recent. I've run Debian sarge on a 128MiB CompactFlash
> card and I'm sure people have done more extreme things than that.
> 
> > If this is the case, maybe there is only theory available regarding
> > whether you can make a computer "run faster" on a 64GB SD card than on a
> > 32GB SD card when cards are otherwise identical.
> 
> So firstly, SD cards in the general case aren't that performant or
> reliable. You can spend more money to get faster and more durable
> ones. The unique selling point of SD cards is the form factor –
> they're small and have no moving parts. They're meant to go in
> devices like cameras, dashcams, cell phones, etc.
> 
> Given two SD cards that differ only in capacity, I would not expect
> their performance to differ. The bigger one may last longer (survive
> more writes) due to you using less of its capacity.
> 
> > I don't really know how swap works on a standard computer, even less how
> > it works when the whole computer runs from/on a SD card.
> 
> It doesn't work any differently, except that swapping onto SD
> generally isn't great because they aren't that fast and they often
> have fairly low write endurance.
> 
> SD cards aren't like SSDs, even though they are both made from a
> form of flash memory. Modern SSDs and flash drives have much better
> write endurance than modern SD cards.
> 
> > Swap is supposed to be make your computer pretend that you have more RAM
> > than it actually has, but if the whole computer is running from/on RAM
> > (or is it?), then what does swap mean?
> 
> I don't know why you have introduced the concept of a computer
> running from memory, as that is a completely different topic. A
> computer running from SD card isn't much different to a computer
> running from an HDD or an SSD. It's just a block device.
> 
> Now, due to the low write endurance of your typical SD card, some
> people — especially those making small single-purpose devices — do
> configure things to load off of the SD card into memory and then run
> largely from memory. This prevents writes into the SD card, thus
> prolonging its life. But that tactic is not in any way required when
> using SD cards and can be done with any block device.
> 
> > On Teres-I with redpill RC2 (now there is a RC3 that I have not yet
> > installed) an unfortunate website with pop up commercials (like dn.se)
> > can eat all performance there is and freeze the mouse for hours. I would
> > guess that could have been fixed on a normal computer with "more RAM",
> > i.e., "more swap"? But is the same true for e.g. Teres-I?
> 
> Sorry I am unfamiliar with Teres and redpill.
> 
> > Second question is if it is meaningful to buy a "super duper blazing
> > fast" SD card for the task to run a whole Debian system?
> 
> If you wish to run a general purpose operating system off of an SD
> card then yes I would suggest that the fastest and more durable one
> you can afford would be a good idea. But also consider a regular
> SSD as some of the low capacity ones may compare favourably in
> price with a specialist SD card.
> 
> > There is a very expensive 64GB SD card from SanDisk that is called
> > Extreme Pro that costs twice as much as same size Extreme Plus. Specs
> > say it is "super duper blazing fast" for video in "Ultra HD 4K", but
> > would Pro also be faster than Plus for the task of running Thunderbird
> > and Firefox at the same time?
> 
> Running big apps like that will benefit more from having enough
> memory. After that is satisfied, fast storage will certainly help.
> You'll have to look at the exact specifications of Plus vs Pro.
> 
> What are you trying to achieve?
> 
> Cheers,
> Andy

Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Jonas Smedegaard]

Quoting Erik Josefsson (2019-06-18 14:26:57)
> This is another quite open question that I probably could research 
> myself, if I had the time.
> 
> As far as I understand, it is quite recent that SD cards are fast and 
> large enough to be able to carry and run an entire Debian instance.
> 
> If this is the case, maybe there is only theory available regarding 
> whether you can make a computer "run faster" on a 64GB SD card than on 
> a 32GB SD card when cards are otherwise identical.
> 
> I don't really know how swap works on a standard computer, even less 
> how it works when the whole computer runs from/on a SD card.
> 
> Swap is supposed to be make your computer pretend that you have more 
> RAM than it actually has, but if the whole computer is running from/on 
> RAM (or is it?), then what does swap mean?

Good explanation on swap: https://www.linuxatemyram.com/


> On Teres-I with redpill RC2 (now there is a RC3 that I have not yet 
> installed) an unfortunate website with pop up commercials (like dn.se) 
> can eat all performance there is and freeze the mouse for hours. I 
> would guess that could have been fixed on a normal computer with "more 
> RAM", i.e., "more swap"? But is the same true for e.g. Teres-I?
> 
> 
> Second question is if it is meaningful to buy a "super duper blazing 
> fast" SD card for the task to run a whole Debian system?
> 
> There is a very expensive 64GB SD card from SanDisk that is called 
> Extreme Pro that costs twice as much as same size Extreme Plus. Specs 
> say it is "super duper blazing fast" for video in "Ultra HD 4K", but 
> would Pro also be faster than Plus for the task of running Thunderbird 
> and Firefox at the same time?

Recent research on SD card performance:
https://github.com/ThomasKaiser/Knowledge/blob/master/articles/A1_and_A2_rated_SD_cards.md


 - Jonas

-- 
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 * Tlf.: +45 40843136  Website: http://dr.jones.dk/

 [x] quote me freely  [ ] ask before reusing  [ ] keep private


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Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Andy Smith]

Hi Erik,

On Tue, Jun 18, 2019 at 02:26:57PM +0200, Erik Josefsson wrote:
> As far as I understand, it is quite recent that SD cards are fast and large
> enough to be able to carry and run an entire Debian instance.

Not really recent. I've run Debian sarge on a 128MiB CompactFlash
card and I'm sure people have done more extreme things than that.

> If this is the case, maybe there is only theory available regarding whether
> you can make a computer "run faster" on a 64GB SD card than on a 32GB SD
> card when cards are otherwise identical.

So firstly, SD cards in the general case aren't that performant or
reliable. You can spend more money to get faster and more durable
ones. The unique selling point of SD cards is the form factor –
they're small and have no moving parts. They're meant to go in
devices like cameras, dashcams, cell phones, etc.

Given two SD cards that differ only in capacity, I would not expect
their performance to differ. The bigger one may last longer (survive
more writes) due to you using less of its capacity.

> I don't really know how swap works on a standard computer, even less how it
> works when the whole computer runs from/on a SD card.

It doesn't work any differently, except that swapping onto SD
generally isn't great because they aren't that fast and they often
have fairly low write endurance.

SD cards aren't like SSDs, even though they are both made from a
form of flash memory. Modern SSDs and flash drives have much better
write endurance than modern SD cards.

> Swap is supposed to be make your computer pretend that you have more RAM
> than it actually has, but if the whole computer is running from/on RAM (or
> is it?), then what does swap mean?

I don't know why you have introduced the concept of a computer
running from memory, as that is a completely different topic. A
computer running from SD card isn't much different to a computer
running from an HDD or an SSD. It's just a block device.

Now, due to the low write endurance of your typical SD card, some
people — especially those making small single-purpose devices — do
configure things to load off of the SD card into memory and then run
largely from memory. This prevents writes into the SD card, thus
prolonging its life. But that tactic is not in any way required when
using SD cards and can be done with any block device.

> On Teres-I with redpill RC2 (now there is a RC3 that I have not yet
> installed) an unfortunate website with pop up commercials (like dn.se) can
> eat all performance there is and freeze the mouse for hours. I would guess
> that could have been fixed on a normal computer with "more RAM", i.e., "more
> swap"? But is the same true for e.g. Teres-I?

Sorry I am unfamiliar with Teres and redpill.

> Second question is if it is meaningful to buy a "super duper blazing fast"
> SD card for the task to run a whole Debian system?

If you wish to run a general purpose operating system off of an SD
card then yes I would suggest that the fastest and more durable one
you can afford would be a good idea. But also consider a regular
SSD as some of the low capacity ones may compare favourably in
price with a specialist SD card.

> There is a very expensive 64GB SD card from SanDisk that is called Extreme
> Pro that costs twice as much as same size Extreme Plus. Specs say it is
> "super duper blazing fast" for video in "Ultra HD 4K", but would Pro also be
> faster than Plus for the task of running Thunderbird and Firefox at the same
> time?

Running big apps like that will benefit more from having enough
memory. After that is satisfied, fast storage will certainly help.
You'll have to look at the exact specifications of Plus vs Pro.

What are you trying to achieve?

Cheers,
Andy

-- 
https://bitfolk.com/ -- No-nonsense VPS hosting

Re: System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[songbird]

Erik Josefsson wrote:
...
> I don't really know how swap works on a standard computer, even less how 
> it works when the whole computer runs from/on a SD card.
>
> Swap is supposed to be make your computer pretend that you have more RAM 
> than it actually has, but if the whole computer is running from/on RAM 
> (or is it?), then what does swap mean?
>
> On Teres-I with redpill RC2 (now there is a RC3 that I have not yet 
> installed) an unfortunate website with pop up commercials (like dn.se) 
> can eat all performance there is and freeze the mouse for hours. I would 
> guess that could have been fixed on a normal computer with "more RAM", 
> i.e., "more swap"? But is the same true for e.g. Teres-I?
>
>
> Second question is if it is meaningful to buy a "super duper blazing 
> fast" SD card for the task to run a whole Debian system?
>
> There is a very expensive 64GB SD card from SanDisk that is called 
> Extreme Pro that costs twice as much as same size Extreme Plus. Specs 
> say it is "super duper blazing fast" for video in "Ultra HD 4K", but 
> would Pro also be faster than Plus for the task of running Thunderbird 
> and Firefox at the same time?

  so much would depend upon the IO bus design for all
of these questions.

  swap is just a place for tasks to be paged out if
your system runs out of memory.

  the contention between swap and the rest of the IO
on the channels would be the deciding factor as to
how much it makes a difference.

  some people now run without any swap space at all
(memory isn't that expensive and so why not).  i don't
because at times i edit large pictures and so the
extra memory space is needed.


  songbird

System on a chip - performance relative size and setup (how can the (Debian) setup make a difference?)

[Erik Josefsson]

This is another quite open question that I probably could research 
myself, if I had the time.


As far as I understand, it is quite recent that SD cards are fast and 
large enough to be able to carry and run an entire Debian instance.


If this is the case, maybe there is only theory available regarding 
whether you can make a computer "run faster" on a 64GB SD card than on a 
32GB SD card when cards are otherwise identical.


I don't really know how swap works on a standard computer, even less how 
it works when the whole computer runs from/on a SD card.


Swap is supposed to be make your computer pretend that you have more RAM 
than it actually has, but if the whole computer is running from/on RAM 
(or is it?), then what does swap mean?


On Teres-I with redpill RC2 (now there is a RC3 that I have not yet 
installed) an unfortunate website with pop up commercials (like dn.se) 
can eat all performance there is and freeze the mouse for hours. I would 
guess that could have been fixed on a normal computer with "more RAM", 
i.e., "more swap"? But is the same true for e.g. Teres-I?



Second question is if it is meaningful to buy a "super duper blazing 
fast" SD card for the task to run a whole Debian system?


There is a very expensive 64GB SD card from SanDisk that is called 
Extreme Pro that costs twice as much as same size Extreme Plus. Specs 
say it is "super duper blazing fast" for video in "Ultra HD 4K", but 
would Pro also be faster than Plus for the task of running Thunderbird 
and Firefox at the same time?



Best regards.

//Erik