Re: [PERFORM] hardware raid suggestions

2004-07-26 Thread Gaetano Mendola
Brian Hirt wrote:
I've  been using the adaptec ZCR raid cards in our servers for a while 
now, mostly small systems with 3 or 6 disks, and we've been very happy 
with them.   However, we're building a new DB machine with 14 U320 15K 
SCA drives, and we've run into a performance bottlenkeck with the ZCR 
card where it just won't scale well.  Without going into too many 
details, we've tested RAID5, RAID10 and RAID50 on pretty much every 
array size from 4-14 disks (raid 50 tests used more drives), using JFS, 
reiserfs and EXT3.  With every different configuration,  performance 
didn't improve after array size became greater than 6 disks..   We used 
various benchmarks, including pgbench with scale factors of 10, 100, 
1000, 5000 and clients of 10, 15, 30 and 45.  We've done many other 
tests and monitoring tools, and we've come to the conclusion that the 
ZCR is the problem.

We're looking into getting an Adaptec 2200S or the Megaraid 320 2x which 
have better processors, and hopefully better performance.  We feel that 
the use of the AIC7930 as the CPU on the ZCR  just doesn't cut it and a 
faster raid controller would work better. Does anyone out there have any 
experience with these cards with postgresql and linux?  If so, would you 
be willing to share your experiences and possibly give a recommendation?

Did you consider the option of use an external storage array ?
We are using the dell emc CX600
http://www.dell.com/downloads/emea/products/pvaul/en/Dell_EMC_cx600_specs.pdf
and I'm forgotting to have a disk behind...

Regards
Gaetano Mendola


---(end of broadcast)---
TIP 4: Don't 'kill -9' the postmaster


Re: [PERFORM] hardware raid suggestions

2004-07-16 Thread Fred Moyer
 We're looking into getting an Adaptec 2200S or the Megaraid 320 2x
 which have better processors, and hopefully better performance.  We
 feel that the use of the AIC7930 as the CPU on the ZCR  just doesn't
 cut it and a faster raid controller would work better. Does anyone out
 there have any experience with these cards with postgresql and linux?
 If so, would you be willing to share your experiences and possibly give
 a recommendation?

I have worked with at least four major name brands of scsi and ide raid
controllers and so far the one I have found to be generally the most
featured and fastest is the ICP Vortex controllers
(http://www.icp-vortex.com/).  It is also more expensive than the others
but has been worth the cost IMHO.  It has a command line utility to
measure disk performance and I believe the source code for it is
available.  I have measured over 200 MB/s reads off these controllers on
3u disk array units.  I'm sure I could have gotten more with additional
tuning.

Fred

---(end of broadcast)---
TIP 4: Don't 'kill -9' the postmaster


[PERFORM] hardware raid suggestions

2004-07-15 Thread Brian Hirt
I've  been using the adaptec ZCR raid cards in our servers for a while 
now, mostly small systems with 3 or 6 disks, and we've been very happy 
with them.   However, we're building a new DB machine with 14 U320 15K 
SCA drives, and we've run into a performance bottlenkeck with the ZCR 
card where it just won't scale well.  Without going into too many 
details, we've tested RAID5, RAID10 and RAID50 on pretty much every 
array size from 4-14 disks (raid 50 tests used more drives), using JFS, 
reiserfs and EXT3.  With every different configuration,  performance 
didn't improve after array size became greater than 6 disks..   We used 
various benchmarks, including pgbench with scale factors of 10, 100, 
1000, 5000 and clients of 10, 15, 30 and 45.  We've done many other 
tests and monitoring tools, and we've come to the conclusion that the 
ZCR is the problem.

We're looking into getting an Adaptec 2200S or the Megaraid 320 2x 
which have better processors, and hopefully better performance.  We 
feel that the use of the AIC7930 as the CPU on the ZCR  just doesn't 
cut it and a faster raid controller would work better. Does anyone out 
there have any experience with these cards with postgresql and linux?  
If so, would you be willing to share your experiences and possibly give 
a recommendation?

--brian
---(end of broadcast)---
TIP 8: explain analyze is your friend


Re: [PERFORM] hardware raid suggestions

2004-07-15 Thread Josh Berkus
Brian,

 We're looking into getting an Adaptec 2200S or the Megaraid 320 2x
 which have better processors, and hopefully better performance.  We
 feel that the use of the AIC7930 as the CPU on the ZCR  just doesn't
 cut it and a faster raid controller would work better. Does anyone out
 there have any experience with these cards with postgresql and linux?
 If so, would you be willing to share your experiences and possibly give
 a recommendation?

Yes, my experience with adaptecs has been universally bad.   I just really 
don't think that the SCSI-2 card company is up to making high-end raid 
cards.

MegaRaid is generally positively reviewed in a lot of places.  Be careful to 
order the battery back-up at the same time as the Raid card; the batteries 
have the annoying habit of going off the market for months at a time.

You should also consider looking into driver issues.   In general, the RAID 
card drivers distributed for Linux simply aren't as good as those the same 
companies write for Windows or Unix.  That may be your issue with the ZCR, as 
well as CPU.

Oh, and don't bother with the upgrade if you're not getting battery backup.  
You need it.

-- 
Josh Berkus
Aglio Database Solutions
San Francisco

---(end of broadcast)---
TIP 5: Have you checked our extensive FAQ?

   http://www.postgresql.org/docs/faqs/FAQ.html


Re: [PERFORM] hardware raid suggestions

2004-07-15 Thread Mark Aufflick
Not sure what your hw platform is, but I always used to get fantastic  
performance from Compaq Smart Array battery backed cards. Note that I  
haven't bought any recently so HP may have hp invent-ed them...

But whatever the brand - if you get a swag of battery backed cache you  
won't know yourself. It's fun to install an OS on them as well - watch  
the drive format and verify take 10 seconds ;)

Another option to look at is outboard raid boxes that present a single  
drive interface to the server - I know people  who swear by them.
--  
Mark Aufflick
  e  [EMAIL PROTECTED]
  w  www.pumptheory.com (work)
  w  mark.aufflick.com (personal)
  p  +61 438 700 647
On 16/07/2004, at 4:07 AM, Brian Hirt wrote:

I've  been using the adaptec ZCR raid cards in our servers for a while  
now, mostly small systems with 3 or 6 disks, and we've been very happy  
with them.   However, we're building a new DB machine with 14 U320 15K  
SCA drives, and we've run into a performance bottlenkeck with the ZCR  
card where it just won't scale well.  Without going into too many  
details, we've tested RAID5, RAID10 and RAID50 on pretty much every  
array size from 4-14 disks (raid 50 tests used more drives), using  
JFS, reiserfs and EXT3.  With every different configuration,   
performance didn't improve after array size became greater than 6  
disks..   We used various benchmarks, including pgbench with scale  
factors of 10, 100, 1000, 5000 and clients of 10, 15, 30 and 45.   
We've done many other tests and monitoring tools, and we've come to  
the conclusion that the ZCR is the problem.

We're looking into getting an Adaptec 2200S or the Megaraid 320 2x  
which have better processors, and hopefully better performance.  We  
feel that the use of the AIC7930 as the CPU on the ZCR  just doesn't  
cut it and a faster raid controller would work better. Does anyone out  
there have any experience with these cards with postgresql and linux?   
If so, would you be willing to share your experiences and possibly  
give a recommendation?

--brian
---(end of  
broadcast)---
TIP 8: explain analyze is your friend

=== 
=
Pain free spam  virus protection by:  www.mailsecurity.net.au
Forward undetected SPAM to:   [EMAIL PROTECTED]
=== 
=



Pain free spam  virus protection by:  www.mailsecurity.net.au
Forward undetected SPAM to:   [EMAIL PROTECTED]

---(end of broadcast)---
TIP 5: Have you checked our extensive FAQ?
  http://www.postgresql.org/docs/faqs/FAQ.html