Re: [gentoo-user] Memory manager

[Wol's lists]

On 19/10/2019 16:24, Mick wrote:
On Saturday, 19 October 2019 14:11:26 bstmad.scientist.at.la...@tutanota.com  
wrote:

Do systems run different memory management when swap is on versus no swap?



The answer to this question is an unqualified yes, although you do not define
your meaning of "different memory management".  The existence of swap space
and the kernel's swappiness setting will change the way memory is dynamically
allocated to processes at runtime and may affect the responsiveness of your
system.


Memory management was massively rewritten roundabout kernel 2.4.

The original swap algorithm NEEDED twice ram as swap. And when Linus 
ripped out all the "optimisation", the vanilla kernels only needed to 
touch swap, and if they didn't have twice ram they would crash.


At that point, the recommendation changed to "no swap is fine, twice or 
more is fine, just don't have swap less than twice ram".


My personal rule is to take the motherboard's max ram, double it, and 
create a swap partition that size on every disk. So my current desktop 
system has 80GB of ram/swap - 4x4GB slots times 2 disk drives. And my 
new system has 4x8GB so that'll be 160GB!!! HOWEVER - Richard Brown of 
SUSE said that's dangerous - if somebody fork-bombs you it'll take a 
long time to fill that much swap and regaining control of your system 
could well be a big red switch job.


Cheers,
Wol

Re: [gentoo-user] Fdisk reports new HD as 10MiB

[Wol's lists]

On 05/07/2019 15:30, Robin Atwood wrote:

Thanks Vladimir, that sounds promising. Can you recommend any GPT
programs (this is new to me)? However the dd utility failed when I
tried to copy my old HD to the new one.


Recommend any gpt programs? fdisk :-) ?

Yes I know it was said it doesn't work, but ime it's been upgraded to 
cope. That said, I always use gdisk now, which is almost the same but 
explicitly handles gpt.


Cheers,
Wol

Re: [gentoo-user] Fdisk reports new HD as 10MiB

[Wol's lists]

On 06/07/2019 15:56, Dale wrote:

Robin Atwood wrote:

On Sat, 6 Jul 2019 09:11:22 +1000
Adam Carter  wrote:


OK panic over! I had shelled into the wrong system! The mystery is
what I was trying to copy to, the machine only has one HD.


lsblk is nice

$ lsblk
NAMEMAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda   8:00 931.5G  0 disk
└─sda18:10 931.5G  0 part /var
nvme0n1 259:00   477G  0 disk
├─nvme0n1p1 259:10 1G  0 part
└─nvme0n1p2 259:20   476G  0 part /

lsblk *is* nice, thanks!

Robin



FYI, it also works when using LVM too.


root@fireball / # lsblk
NAME  MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda 8:0    1 149.1G  0 disk
├─sda1  8:1    1 384.3M  0 part /boot
├─sda2  8:2    1 1K  0 part
├─sda5  8:5    1   957M  0 part
├─sda6  8:6    1  23.3G  0 part /
└─sda7  8:7    1 124.5G  0 part
   ├─OS-usr    254:0    0    35G  0 lvm  /usr
   ├─OS-var    254:1    0    32G  0 lvm  /var
   └─OS-swap   254:2    0    12G  0 lvm  [SWAP]
sdb 8:16   1   2.7T  0 disk
└─sdb1  8:17   1   2.7T  0 part
   └─Home2-Home2   254:3    0   8.2T  0 lvm  /home
sdc 8:32   1   5.5T  0 disk
└─sdc1  8:33   1   5.5T  0 part
   └─Home2-Home2   254:3    0   8.2T  0 lvm  /home
sdd 8:48   1 698.7G  0 disk
└─sdd1  8:49   1 698.7G  0 part
   └─backup-backup 254:4    0 698.6G  0 lvm  /backup
sr0    11:0    1 3G  0 rom
root@fireball / #


What about lsdrv (as per the raid wiki)?

https://raid.wiki.kernel.org/index.php/Asking_for_help

That handles pretty much everything.

Cheers,
Wol

Re: [gentoo-user] Re: Picking out a printer. Questions.

[Wol's lists]

On 27/04/2019 18:04, Peter Humphrey wrote:

On Saturday, 27 April 2019 16:42:39 BST Wols Lists wrote:



Laser printers cost up front, but once I've paid for this set of
cartridges I'm probably set up for a couple of years. Just don't expect
modern lasers to go on and on, and budget to replace it ... :-)


Not like my old Kyocera, which just keeps soldiering on.

My old QMS only died because I couldn't source any new cartridges :-( 
that was a cheapo printer too but I think the drivers were for Win95, 
says how old it was ...


(It came in two versions, I forked out the extra fiver for PCL support 
over and above WinPrinter.)


Cheers,
Wol

Re: [gentoo-user] USB external hard drives

[Wol's lists]

On 15/04/2019 18:32, Mick wrote:

f) Re-enable Windows Updates and page file.


Do NOT re-enable windows hibernate (note that Windows will do it itself 
on an update :-( if you want to mount your windows drive from linux.


I run OpenSUSE on my laptop, and this mess repeatedly breaks my linux 
boot when I don't shut down windows properly. Mount crashes when fed a 
hibernated windows disk and dumps me in to systemd's konsole :-(


(When you select "shut down", Windows "helpfully" does some form of 
hibernate - it does NOT shut down unless you faff about to force it to 
shut down.)


Cheers,
Wol

Re: [gentoo-user] RAID-1 on secondary disks how?

[Wol's lists]

On 29/01/2019 19:41, Grant Taylor wrote:
The kernel /must/ have (at least) the minimum drivers (and dependencies) 
to be able to boot strap.  It doesn't matter if it's boot strapping an 
initramfs or otherwise.


All of these issues about lack of a driver are avoided by having the 
driver statically compiled into the kernel.


I'm not sure to what extent it's true of 64-bit hardware, but one of the 
big problems with non-module kernels is actually being able to load them 
into the available ram ... something to do with BG's "640K should be 
enough for anyone".


Cheers,
Wol

Re: [gentoo-user] RAID-1 on secondary disks how?

[Wol's lists]

On 28/01/2019 16:56, Peter Humphrey wrote:

I must be missing something, in spite of following the wiki instructions. Can
someone help an old duffer out?


Gentoo wiki, or kernel raid wiki?

Cheers,
Wol

Re: [gentoo-user] RAID-1 on secondary disks how?

[Wol's lists]

On 29/01/2019 19:01, Rich Freeman wrote:

It would surely be a bug if the kernel were capable of manipulating RAIDs, but 
not of initialising
and mounting them.



Linus would disagree with you there, and has said as much publicly.
He does not consider initialization to be the responsibility of kernel
space long-term, and prefers that this happen in user-space.

Some of the lvm and mdadm support remains for legacy reasons, but you
probably won't see initialization of newer volume/etc managers
supported directly in the kernel.

Actually, the kernel isn't capable of manipulating raid. The reason you 
need raid 0.9 (or 1.0, actually) is that all the raid metadata is at the 
*end* of the partition, so the system boots off the file-system 
completely ignorant that it's actually a raid. The raid then gets 
assembled and when root is remounted rw, it's the raid version that's 
mounted not a single-disk filesystem.


In other words, if you have sda1 and sdb1 raided together as your root, 
the system will boot off a read-only sda1 before switching to a 
read-write md1.


Cheers,
Wol

Re: [gentoo-user] RAID-1 on secondary disks how?

[Wol's lists]

On 29/01/2019 16:48, Alan Mackenzie wrote:

Hello, All.

On Tue, Jan 29, 2019 at 09:32:19 -0700, Grant Taylor wrote:

On 01/29/2019 09:08 AM, Peter Humphrey wrote:

I'd rather not have to create an initramfs if I can avoid it. Would it
be sensible to start the raid volume by putting an mdadm --assemble
command into, say, /etc/local.d/raid.start? The machine doesn't boot
from /dev/md0.



Drive by comment.



I thought there was a kernel option / command line parameter that
enabled the kernel to automatically assemble arrays as it's
initializing.  Would something like that work for you?



I have no idea where that is in the context of what you're working on.


I use mdadm with a RAID-1 pair of SSDs, without an initramfs (YUCK!).
My root partition is on the RAID.

For this, the kernel needs to be able to assemble the drives into the
raid at booting up time, and for that you need version 0.90 metadata.
(Or, at least, you did back in 2017.)


You still do. 0.9 is deprecated and bit-rotting. If  it breaks, nobody 
is going to fix it!!!


My command for building my array was:

 # mdadm --create /dev/md2 --level=1 --raid-devices=2 \
 --metadata=0.90 /dev/nvme0n1p2 /dev/nvme1n1p2.

However, there's another quirk which bit me: something in the Gentoo
installation disk took it upon itself to renumber my /dev/md2 to
/dev/md127.  I raised bug #539162 for this, but it was decided not to
fix it.  (This was back in February 2015.)

This is nothing to do with gentoo - it's mdadm. And like with sdX for 
drives, it's explicitly not guaranteed that the number remains 
consistent. You're supposed to use names now, eg /dev/md/root, or 
/dev/md/home for example.


Cheers,
Wol

Re: [gentoo-user] system clock screwed up since last ntpd update...

[Wol's lists]

On 14/12/2018 18:45, tu...@posteo.de wrote:

ntpd is running and below /etc no configuration update is missing.

The only thing I missing currentlu is the correct time display...


What is it that is displaying the date? I often have that sort of 
problem where all of a sudden the clock starts displaying UTC when it 
should be displaying GMT/BST.


Thing is, it's the KDE Clock, and the KDE settings that are messed up.

Cheers,
Wol

Re: [gentoo-user] Scanners, sane and driver support question

[Wol's lists]

On 12/11/2018 14:34, Mick wrote:

The problem I've had with inkjet is that the ink dries out
unless used daily, the print heads clog up and as others have mentioned
replacing them costs more than the printer.


Hang on a sec, I was talking about a *LASER*! £350 for the printer, 
£400+ for a set of cartridges.


And my last two lasers were "free with 3 sets of toners" so again the 
toners cost more than the printer :-)


Okay compatible cartridges are a lot cheaper (I could get a complete set 
for about £100), but I suspect my next set of cartridges at least will 
be genuine HP. Provided I use only HP my printer is warrantied for three 
years, and I suspect that by the time I've used that first set of 
replacement cartridges, the three years will be up :-)


(Still, I can't complain, the first laserjet I bought (for a company) 
cost £3000.) I think if you buy genuine manufacturer cartridges, it's 
typical for laser toners to cost similar (or more) than the printer, but 
you do get a lot more pages to a set of toners, than a set of inks.


Cheers,
Wol

Re: [gentoo-user] Scanners, sane and driver support question

[Wol's lists]

On 11/11/2018 14:29, Dale wrote:

Thanks for the info.  I figured someone may have a little better idea on
this.  After some more digging, I found a ScanJet 4570C which is
actually a little better than the others I was looking at.  So, I bought
it.  It shows complete but appears to be still maintained.


I've got an HP MFP 477 (not cheap - nigh on £400), but it has what I 
call "push scanning". Configure samba, point the printer at it, and when 
you hit "scan" it dumps a pdf, or jpeg, or whatever, in the samba folder 
you told it to.


Cheers,
Wol

Re: [gentoo-user] Hard drive storage questions

[Wol's lists]

On 11/11/2018 00:45, Dale wrote:

This is a lot to think on.  Money wise, and maybe even expansion wise, I
may go with the PCI SATA cards and add drives inside my case.  I have
plenty of power supply since it pulls at most 200 watts and I think my
P/S is like 700 or 800 watts.  I can also add a external SATA card or
another USB drive to do backups with as well.  At some point tho, I may
have to build one of those little tiny systems that is basically nothing
but SATA drive controllers and ethernet enabled.  Have that sitting in a
closet somewhere running some small OS.  I can always just move the
drives from my system to it if needed.


https://raid.wiki.kernel.org/index.php/What_is_RAID_and_why_should_you_want_it%3F

(disclaimer - I wrote it :-)

You've got a bunch of questions to ask yourself. Is this an amateur 
setup (sounds a bit like it in that it appears to be a home server) or 
is it a professional "money no object" setup.


Either way, if you spend good money on good disks (WD Red, Seagate 
Ironwolf, etc) then most of your investment will be good to re-purpose. 
My current 3TB drives are Barracudas - not a good idea for a 
fault-tolerant system - which is why the replacements are Ironwolves.


Then, as that web-page makes clear, do you want your raid/volume 
management to be separate from your filesystem - mdraid/lvm under ext4 - 
or do you want a filesystem that is hardware-aware like zfs or xfs, or 
do you want something like btrfs which tries to be the latter, but is 
better used as the former.


One thing to seriously watch out for - many filesystems are aware of the 
underlying layer even when you don't expect it. Not sure which 
filesystem it is but I remember an email discussion where the filesystem 
was aware it was running over mdraid and balanced itself for the 
underlying disks. The filesystem developer didn't realise that mdraid 
can add and remove disks so the underlying structure can change, and the 
recommendation was "once you've set up the raid, if you want to grow 
your space move it to a new raid".


At the end of the day, there is no perfect answer, and you need to ask 
yourself what you are trying to achieve, and what you can afford.


Cheers,
Wol

Re: [gentoo-user] CUPS remote printing drives me crazy

[Wol's lists]

On 13/09/2018 12:57, Heiko Baums wrote:

Wifi isn't the most reliable option.



I didn't have a problem yet with printing or scanning over Wifi.


You're lucky !!!

Okay, my main problem is the broadband connection that takes out the 
router, but my house is NOT wi-fi friendly, and that's pretty typical.


I will now ALWAYS pick wired over wi-fi if possible. If (as I hope to do 
in the not-too-distant future) I get the chance to design or do up a 
house, I would make sure I had hidden wiring in pretty much every room!


Cheers,
Wol

Re: [gentoo-user] [OT] Is that possible or nonsense (3D-Printing via WiFi) ?

[Wol's lists]

On 03/09/18 05:50, J. Roeleveld wrote:

If the printer requires a near constant stream of data over the USB port, you 
might want to look into a physical cable instead of wifi for the communication.


And DON'T hang ANYTHING else on USB (except, of course, the keyboard and 
mouse).


Actually, if you've got separate USB-1, -2, and -3 ports, make sure it's 
the only thing on the -3 ports. Sharing devices on a hub (and a lot of 
mobos have internal hubs so you don't know if ports are shared or not) 
can cause all sorts of grief if you're unlucky.


Cheers,
Wol

Re: [gentoo-user] Re: Update circle

[Wol's lists]

On 23/08/18 11:25, Adam Carter wrote:

The machine is actually a server, which just sat in a corner doing its
job perfectly. That's one of the reasons it wasn't updated: if it ain't
broken, don't fix it.


Any system that is not getting software updates is broken to some 
degree, just in a subtle way.


Trimming your /var/lib/portage/world file and removing the trimmed 
packages can make the update less painful. I sometimes remove non-system 
packages I want, then reinstall again later to get through difficult 
upgrades.


Bit late to the party, but yes this is normally my approach.

If emerge lists a bunch of packages it thinks it can build, I explicitly 
just update them (on several occasions that has "miraculously" cleared 
the conflicts and the next global emerge just roars away).


I wish there was a portage option that said "don't give up, just emerge 
what you can".


If there are conflicts on something that doesn't appear crucial to the 
system, I just "emerge -C" it, and make a note to put it back later.


My current home system is like this one, well out of date, but I'm 
planning to replace not fix it, because it's a multi-user system and 
*relies* on kdm which has, iirc, been deprecated and is not in kde5. 
Upgrading that is a task I do NOT fancy ... :-)


Cheers,
Wol

Re: [gentoo-user] [Maybe OT]: Instability of system

[Wol's lists]

On 11/06/18 16:30, R0b0t1 wrote:

Federal law implies a warranty of fitness for a particular purpose*
from the seller, not the manufacturer. You can take it up with them.
The statute of limitations is 4 years. Make them deal with AMD.


Please read the parent post !!!

The seller no longer exists, so that is not an option.

Federal law is irrelevant, as the OP is about 4000 miles outside their 
jurisdiction.


I believe the OP and AMD are the same nationality, and that is nowhere 
near the American continent, let alone the US.


Cheers,
Wol

Re: [gentoo-user] Enable "regular" network traffic when using VPN

[Wol's lists]

On 10/06/18 17:53, Mick wrote:

On Sunday, 10 June 2018 01:31:50 BST Hilco Wijbenga wrote:

Okay, with all that advice, I gave it another try. I'm also setting up
a VirtualBox for my WFH stuff and VB wants to use 10.0.0.0 for its
networking. I've changed this to 172.16.0.0 so now I can easily tell
that network from work network (which seems to use 10.25.0.0)

I wanted to add a route to NetworkManager's VPN connection. It wants
Address, Network, Gateway, and Metric so I gave it "10.0.0.0",
"255.0.0.0" (this one shows up automatically), "207.x.y.z", "1". But
then VPN fails to start with the complaint that the configuration is
invalid.

So I tried what I think is the same on the CL:

$> route add -net 10.0.0.0/8 gw "207.x.y.z" metric 1
SIOCADDRT: Network is unreachable

So apparently, it's not quite as straightforward as I thought it might be.
:-)


Ahh!  If you're trying to set this up within a VM, this adds a whole new layer
of complexity.  I assume you're setting up a bridge between host and guest
device(s)?

No if he's assigned 172.16/16 to the VM network he hasn't. VB defaults 
to a NAT'd network and it's always given me grief. I was going to 
suggest he switched to bridged.


In settings, change the network adaptor type to bridged, and then the VM 
will get its settings and IP address from the DHCP server serving the 
local network. Makes things MUCH easier.


Cheers,
Wol

Re: [gentoo-user] NFS and user IDs

[Wol's lists]

On 09/06/18 18:09, Rich Freeman wrote:

I feel like this is something that Windows natively gets "better" than
POSIX.  They have a concept of UIDs being specific to a machine or
authentication server (or domain as they call it), and this concept is
enforced at the host level.  That said, I'm sure this approach has its
downsides as well, in particular it is certainly more complex and at
work we practically forbid any kind of windows ACLs at anything other
than the top mount level because it is so hard to control.


Windows is better than POSIX?! That doesn't say much for POSIX then, 
seeing as I feel Windows ACLs are overly complex and difficult!


Okay, ACLs assume a directory structure, which have serious problems 
with Unix hard links, so I can understand the two features not mapping 
on to each other very well. In particular, if an object does not have a 
specific acl, it's supposed to inherit from its parent, but if you have 
hard links which parent does it inherit from?


The system I used which had ACLs, I *think* when you logged in to any 
machine, you could tell it to authenticate against a different machine 
so it must have had some machine/identity pair.


Then ACLs were simplicity itself as well, because they were 
user,group,other. If a user was named, that was what they got. If they 
weren't named, they got the sum of all the groups they belonged to. And 
if none of their groups were named, they just got the other permissions.


So if you wanted someone to get LESS than the sum of their groups, you 
just gave them personally what you wanted, and that was that.


Cheers,
Wol

Re: [gentoo-user] Re: Spectre-NG

[Wol's lists]

On 09/05/18 23:50, Ian Zimmerman wrote:

Code may be "security-sensitive" but buggy.  Is the compiler writer
really responsible for guessing what the programmer meant to accomplish
with buggy code?


What do you mean by "buggy"?


  It would of course be preferable if the compiler could
just abort with an error when it detects UB, but that turns out to be
very hard to impossible in the case of C.  That's just a built in
problem with the language.


So if the compiler can't detect undefined behaviour, how the hell do you 
expect the programmer to?


Oh - and please explain - what is buggy about wanting the following 
program to compile and actually *do* what the code is asking, rather 
than compiling to a no-op ...


int main () {
  int a, b, c;
  a = 2;
  b = 4;
  c = 6;
}

Note I did say the problem is almost invariably when hardware gets 
involved - what happens if it's


int main () {
  void *a;
  a = 0x00ff;
  *a = 6;
}

and 0x00ff is the address of your network adaptor? Do you want THAT to 
be optimised away "because it doesn't do anything"?


That's why I expect LVM/Clang is much better - because I believe Intel 
is heavily involved they provide guarantees about how the compiler will 
interact with hardware, when the C standard explicitly avoids specifying 
it (imho, the standard should require a compiler to document how it 
handles things like that ...). (Yes I believe there is some compiler 
option to make that work, but I'm pretty certain that either is or was 
undefined behaviour to start with? And if it is now standard, it's 
probably because some clever idiot optimised the "code which doesn't do 
anything" away and they had to define a way of stopping it?)


Cheers,
Wol

Re: [gentoo-user] [OT] Re: Firefox and addons no longer supported question

[Wol's lists]

On 05/04/18 12:23, Mick wrote:

On Thursday, 5 April 2018 09:57:54 BST Peter Humphrey wrote:

On Wednesday, 4 April 2018 19:12:23 BST Wol's lists wrote:

On 02/04/18 21:50, Philip Webb wrote:

180402 Dale wrote:

After each period at the end of a sentence, I put in two spaces, not
one.
Something I was taught years ago somewhere and still do.
I only put one after a comma tho.


That is correct professional secretarial style, which I always follow
too.


I was taught to always start every paragraph with an indent. Which I
believe is against "professional secretarial style".


There seem to be two alternative styles: either indent the start of a
paragraph, or leave a blank line before it. I learned at an early age that
an indent marked a new para (not some empty space that usually just
happened to be left at the end of the line before) - I remember arguing
that point at primary school, some time in 1952 - 1954.


I don't know the correct terminology, but if the title is centre-aligned the
paragraphs' first line ought to have a single space indent.  When I was in
primary school this was the prevailing style.


Don't you mean a single tab indent :-) This was the style I was supposed 
to write in (with a *fountain* pen, at *primary* school - probably at 
about year 5 or 6), and the indent was about the space of the word "and".


With the advent of word processors the titles as well as the paragraphs became
left-aligned with no space at their start, but this may have been a
typesetting style BC (Before Computers).  :-)

When I started using a typewriter, the indent was always 5 spaces. And I 
kept that style when I moved to a word processor (despite being told off 
by the typists). When they typed up my letters I think I told them "it's 
my letter, do it my way" :-)


(I *hate* using the word "secretary" to refer to a typist - a proper 
Secretary has a legally-recognised, degree-class law qualification - my 
mum was one.)


Cheers,
Wol

Re: [gentoo-user] [OT] Re: Firefox and addons no longer supported question

[Wol's lists]

On 05/04/18 09:57, Peter Humphrey wrote:

Indeed, and that's more-or-less how I see the usual American insistence on a
comma before the "and" before the last item in a list, even though it gets in
the way and introduces ambiguity - the infamous Oxford comma.

But that's a whole new can of worms.


I think we should table that ...

I was taught that a comma separates items in a list, an "and" joins 
them, and you do not mix the two! Indeed, when I did my English GCE 
(that dates it!) I believe the Examining Board Style Guide explicitly 
enforced that rule, and you lost marks for breaking it.


Personally, I do what feels right and I suspect the longer the list, the 
more likely I am to use a comma before the last and.


But again this comes down to another moan of mine - why is "The Queen's 
English" considered "correct", while let's say Yorkshire Dialect is 
considered "wrong", when said dialect is hundreds of years old but the 
Queen's English has probably only been around for about a century.


I'm all for standards, but the complaint should not be "it's wrong", but 
"it breaks the standard", and importantly you need to know *which* standard!


Cheers,
Wol

Re: [gentoo-user] Re: Firefox and addons no longer supported question

[Wol's lists]

On 02/04/18 21:50, Philip Webb wrote:

180402 Dale wrote:

After each period at the end of a sentence, I put in two spaces, not one.
Something I was taught years ago somewhere and still do.
I only put one after a comma tho.

That is correct professional secretarial style, which I always follow too.

I was taught to always start every paragraph with an indent. Which I 
believe is against "professional secretarial style".


Different horses, different courses. I believe the indent was dropped to 
save a keystroke, so why the double-space is there (requiring an extra 
keystroke) I don't know.


And why use secretarial style when you're typesetting? One is for 
letters, the other is typically for books ... that's the trouble with 
all this Artificial Stupidity - it blindly enforces rules that are 
irrelevant (or even wrong!!!) for the current scenario.


Cheers,
Wol

Re: [gentoo-user] Re: /var/tmp on tmpfs

[Wol's lists]

On 10/02/18 20:06, Rich Freeman wrote:

On Sat, Feb 10, 2018 at 2:52 PM, Kai Krakow  wrote:

Am Sat, 10 Feb 2018 19:38:56 + schrieb Wols Lists:


On 10/02/18 18:56, Kai Krakow wrote:

role and /usr takes the role of /, and /home already took the role of
/usr (that's why it's called /usr, it was user data in early unix). The


Actually no, not at all. /usr is not short for USeR, it's an acronym for
User System Resources, which is why it contains OS stuff, not user
stuff. Very confusing, I know.


 From https://www.tldp.org/LDP/Linux-Filesystem-Hierarchy/html/usr.html:


In the original Unix implementations, /usr was where the home
directories of the users were placed (that is to say, /usr/someone was
then the directory now known as /home/someone). In current Unices, /usr
is where user-land programs and data (as opposed to 'system land'
programs and data) are. The name hasn't changed, but it's meaning has
narrowed and lengthened from "everything user related" to "user usable
programs and data". As such, some people may now refer to this
directory as meaning 'User System Resources' and not 'user' as was
originally intended.


So, actually the acronym was only invented later to represent the new
role of the directory. ;-)



A bit more of history here:

http://www.osnews.com/story/25556/Understanding_the_bin_sbin_usr_bin_usr_sbin_Split

Fascinating. And I made a typo, which is interesting too - I always knew 
it as Unix System Resources - typing "user" was a mistake ... I wonder 
how much weird info is down to mistakes like that :-)


Cheers,
Wol

Re: [gentoo-user] /var/tmp on tmpfs

[Wol's lists]

On 09/02/18 00:02, Rich Freeman wrote:

On Thu, Feb 8, 2018 at 6:18 PM, Wol's lists<antli...@youngman.org.uk>  wrote:

/var/tmp is defined as the place where programs store stuff like crash
recovery files. Mounting it tmpfs is going to screw up any programs that
reply on that*defined*  behaviour to recover after a crash.


Care to cite an example of such a program in the Gentoo repo?  I
certainly can't think of any, and I've been running with /var/tmp on
tmpfs for over a decade.


I don't know of any. I was involved with the LSB ages ago, and they were 
involved with the FHS, and that was just one of the things I picked up - 
the FHS specifically says /var/tmp is for files that are temporary but 
not volatile - files that programs are supposed to clean up behind them 
but are saved if the program is prevented from deleting them.


Cheers,
Wol

Re: [gentoo-user] /var/tmp on tmpfs

[Wol's lists]

On 08/02/18 20:56, Grant Taylor wrote:

On 02/08/2018 10:11 AM, gevisz wrote:
And I am going to set the whole /var/tmp on tpmfs instead of just 
/var/tmp/portage


Is it ok?


I don't know about the context of emerging, but I do know about the 
context of /var/tmp being volatile.


More specifically, /var/tmp is traditionally supposed to be non-volatile 
(across reboots).


Comparatively the contents of /tmp can be volatile (across reboots).

I would advise against mounting /var/tmp on tmpfs.


EMPHATICALLY YES.

/tmp is defined as being volatile - stuff can disappear at any time.

/var/tmp is defined as the place where programs store stuff like crash 
recovery files. Mounting it tmpfs is going to screw up any programs that 
reply on that *defined* behaviour to recover after a crash.


Mounting /var/tmp/portage as tmpfs is perfectly fine as far as I know - 
I do it myself.


Cheers,
Wol

Re: [gentoo-user] [OT] A little help for non-native English speakers

[Wol's lists]

On 02/02/18 17:28, Grant Taylor wrote:

On 02/02/2018 01:10 AM, Neil Bothwick wrote:

We could use Perl.


I see your Perl and raise you Lisp.


Or the "language to replace all languages", PL/1

Cheers,
Wol

Re: [gentoo-user] Re: [OT] A little help for non-native English speakers

[Wol's lists]

On 02/02/18 00:08, Jack wrote:


 >> "eg", which, phonetically, is the start of the word "example".
 >
 > A non-native speaker of English, or a non-native speaker of Latin?


And Latin's descendants (which are mutually comprehensible) are actually 
the most widely spoken first language in Europe. I always thought Europe 
should adopt Modern Latin (however you care to define it) as its main 
official language.


(Spanish, Portuguese, and Italian put together are very similar and are 
larger than any other grouping of similar European language, excluding 
perhaps Russian which is spoken mostly by non-EU nationals.)


Cheers,
Wol

Re: [gentoo-user] kernel 4.9.77 error segfault in compile.

[Wol's lists]

On 23/01/18 17:35, Rich Freeman wrote:

Wonderful ... just finished a complete reload of Gentoo. Now have to
redo it again ...
... the mistake? I used ext2/ext3 for the fs.


Abandoning ext4 over retpolines/etc seems a bit drastic.  My guess is
that there is a bug in the latest kernel that will get fixed, or maybe
a bug in gcc (which needs to be patched for spectre anyway).


Did you use the ext2/ext3 driver? I believe it's been abandoned?

The ext4 driver is compatible with 2/3 file systems, so as I understand 
it all development effort goes into the ext4 driver, and any problems 
with the older drivers is likely to be met with "upgrade your driver".


So if you were using that driver, it could be suffering bit-rot.

Cheers,
Wol

Re: [gentoo-user] Kernel upgrade confusion

[Wol's lists]

On 30/12/17 19:11, Mick wrote:

to remove the symlink pointing to the previous kernel,
to create a new symlink to the new kernel sources directory,


Or, to use the supplied gentoo tools ...

eselect kernel list

eselect kernel set n

to see what kernels the system thinks are available, and to change the 
current selected kernel.


Note that "emerge --depclean" will clear out all the files IT KNOWS 
ABOUT in /usr/src, so if you don't clean it out manually it will be full 
of debris from previous kernels - basically all the output of make.


But eselect kernel won't show those as available because depclean clears 
up all the references to them.


Cheers,
Wol

Re: [gentoo-user] Kernel upgrade confusion

[Wol's lists]

On 30/12/17 18:43, Jalus Bilieyich wrote:

Recently there was a kernel update and I don't want to reconfigure it
from scratch. In the official documentation, it told me to move the old
.config into the new kernel source tree and type
make oldconfig

This is where I'm confused; which .config file (/proc/config.gz or
/boot/config) and where in the kernel source tree do I put this file in.



/usr/src/linux/.config

Cheers,
Wol

Re: [gentoo-user] Choice of TLD for internal network

[Wol's lists]

On 18/12/17 13:56, Michael Orlitzky wrote:

On 12/17/2017 09:05 PM, Peter Humphrey wrote:

Hello list,

I've been running Linux systems since 1994, calling my private LAN mynet
(bowdlerised). Now I come to install neth server on one machine, it insists
that I tell it a domain name with at least two dots in it. But I don't have
a standard TLD.

What do you all call your local LANs? Following Google hints, it looks as
though I may have to change all .mynet references to .mynet.internal.


You should probably buy a TLD. It's stupid, but there are no reserved
top-level domain names for internal use. There used to be four[0],

   * test
   * example
   * invalid
   * localhost

There was no proscribed behavior for those TLDs, so you were free to use
them for your internal network. Then along came rfc6761[1], which tells
people how to treat those four names. In particular,

My router defaults, iirc, to .local. And I thought .home also did the 
same sort of thing.


See RFCs 7788 for .home, and 8244 for .local

It seems to me that 7788 defines .home, although it appears it did not 
do it properly.


I think .local was correctly added to 6761, so that domain CAN be used 
as your private network's TLD.


Cheers,
Wol

Re: [gentoo-user] Re: Is gnome becoming obligatory?

[Wol's lists]

On 10/12/17 23:08, Walter Dnes wrote:

Oddly enough, although the details are different, that passage I've
quoted pretty accurately describes how I feel about Gnome ...:-)



   I can't find it right now on Google, but I vaguely remember that
Lennart asked the Gnome people to make systemd a hard dependancy.  Not
much later logind, which is required by Gnome, picks up systemd as a
hard dependancy.


Imho that's no problem. If a higher level has a hard dependency on a 
lower level, that's no surprise. And why should I care if someone else's 
desktop pulls in any particular low-level plumbing. :-)


BUT! If my choice of low-level plumbing (systemd) pulls in a desktop I 
don't want that is a BIG PROBLEM. If I'm running headless, I don't even 
WANT a desktop !!! I more and more get the feeling that linux is 
standardising on the Gnome desktop, which I really just DO NOT get on with.


Cheers,
Wol

Re: [gentoo-user] Basic questions about Distcc

[Wol's lists]

On 03/11/17 18:02, Rich Freeman wrote:

My understanding is that the preprocessing is all done on the target
machine, and the remote workers take all their marching orders from
there.  The contents of CFLAGS, libraries, and so on don't matter on
the workers.  You can build a program that requires qt using distcc
workers that don't have qt installed, because all the includes are
already resolved by the time the source code reaches them and linking
is done later.


Yup. If you're cross-compiling (like I was - a mix of 32 and 64 bit), 
provided all machines are set up correctly it works fine. BUT. That's if 
the "master" is compiling for itself and just sharing out the work.


But if all the machines are similar architecture (like mine are now all 
x86_64) you can do what I do - the fastest machine builds everything and 
makes binary install files, and the slower machines just install the 
binaries. (Or actually, the slower machine builds everything, because 
the faster machine has a habit of falling over during builds :-(


Cheers,
Wol

Re: [gentoo-user] Basic questions about Distcc

[Wol's lists]

On 03/11/17 16:54, Lasse Pouru wrote:

I have a bunch of old laptops that large builds such as texlive and ghc fail 
on, I'm assuming because of insufficient memory and disk space. If I've 
understood correctly, with Distcc I could build everything on my main desktop 
PC and have the binaries transferred through network? How does this work, 
exactly, and is it a lot of work to set up? I currently have no networking 
devices besides a single modem/router, would something more be required?

No. What distcc does is spread compilation across multiple machines to 
save time, so if it blows up on those machine currently, there's no 
guarantee it won't blow up with distcc.


What I do is make sure my flags and stuff match across all machines, 
then compile using the -bk flags (I can't remember which says "create 
binary if it doesn't exist" and which is "use binary if it exists"). 
That way, it builds on the machine that works, and uses the binary on 
the machines that don't.


Oh - and it's definitely possible you've got dodgy ram. I gather it's 
not uncommon for ram to work perfectly until gcc stresses it on a big 
build at which point everything comes crashing down ...


Cheers,
Wol