Re: [PERFORM] RAID stripe size question

2006-08-04 Thread Mikael Carneholm
> WRT seek performance, we're doing 2500 seeks per second on the Sun/Thumper on 36 disks. Luke, Have you had time to run benchmarksql against it yet? I'm just curious about the IO seeks/s vs. transactions/minute correlation... /Mikael ---(end of broadcast)---

Re: [PERFORM] RAID stripe size question

2006-08-03 Thread Merlin Moncure
On 8/3/06, Luke Lonergan <[EMAIL PROTECTED]> wrote: Merlin, > moving a gigabyte around/sec on the server, attached or no, > is pretty heavy lifting on x86 hardware. Maybe so, but we're doing 2GB/s plus on Sun/Thumper with software RAID and 36 disks and 1GB/s on a HW RAID with 16 disks, all SA

Re: [PERFORM] RAID stripe size question

2006-08-02 Thread Luke Lonergan
Merlin, > moving a gigabyte around/sec on the server, attached or no, > is pretty heavy lifting on x86 hardware. Maybe so, but we're doing 2GB/s plus on Sun/Thumper with software RAID and 36 disks and 1GB/s on a HW RAID with 16 disks, all SATA. WRT seek performance, we're doing 2500 seeks per s

Re: [PERFORM] RAID stripe size question

2006-08-02 Thread Merlin Moncure
On 7/18/06, Alex Turner <[EMAIL PROTECTED]> wrote: Remember when it comes to OLTP, massive serial throughput is not gonna help you, it's low seek times, which is why people still buy 15k RPM drives, and why you don't necessarily need a honking SAS/SATA controller which can harness the full 1066MB

Re: [PERFORM] RAID stripe size question

2006-07-18 Thread Milen Kulev
According to http://www.pcguide.com/ref/hdd/perf/raid/concepts/perfStripe-c.html, it seems to be the other way around? ("As stripe size is decreased, files are broken into smaller and smaller pieces. This increases the number of drives that an average file will use to hold all the blocks contain

Re: [PERFORM] RAID stripe size question

2006-07-18 Thread Scott Marlowe
--Original Message- > >From: Scott Marlowe <[EMAIL PROTECTED]> > >Sent: Jul 18, 2006 3:37 PM > >To: Alex Turner <[EMAIL PROTECTED]> > >Cc: Luke Lonergan <[EMAIL PROTECTED]>, Mikael Carneholm <[EMAIL PROTECTED]>, > >Ron Peacetree <[EMAIL PR

Re: [PERFORM] RAID stripe size question

2006-07-18 Thread Ron Peacetree
c: Luke Lonergan <[EMAIL PROTECTED]>, Mikael Carneholm <[EMAIL PROTECTED]>, >Ron Peacetree <[EMAIL PROTECTED]>, pgsql-performance@postgresql.org >Subject: Re: [PERFORM] RAID stripe size question > >On Tue, 2006-07-18 at 14:27, Alex Turner wrote: >> This is a great

Re: [PERFORM] RAID stripe size question

2006-07-18 Thread Scott Marlowe
On Tue, 2006-07-18 at 14:27, Alex Turner wrote: > This is a great testament to the fact that very often software RAID > will seriously outperform hardware RAID because the OS guys who > implemented it took the time to do it right, as compared with some > controller manufacturers who seem to think i

Re: [PERFORM] RAID stripe size question

2006-07-18 Thread Alex Turner
This is a great testament to the fact that very often software RAID will seriously outperform hardware RAID because the OS guys who implemented it took the time to do it right, as compared with some controller manufacturers who seem to think it's okay to provided sub-standard performance. Based on

Re: [PERFORM] RAID stripe size question

2006-07-18 Thread Luke Lonergan
Title: Re: [PERFORM] RAID stripe size question Mikael, On 7/18/06 6:34 AM, "Mikael Carneholm" <[EMAIL PROTECTED]> wrote: > However, what's more important is the seeks/s - ~530/s on a 28 disk > array is quite lousy compared to the 1400/s on a 12 x 15Kdisk array I&

Re: [PERFORM] RAID stripe size question

2006-07-18 Thread Mikael Carneholm
> This is a relatively low end HBA with 1 4Gb FC on it. Max sustained IO on it is going to be ~320MBps. Or ~ enough for an 8 HD RAID 10 set made of 75MBps ASTR HD's. Looking at http://h30094.www3.hp.com/product.asp?sku=2260908&extended=1, I notice that the controller has a Ultra160 SCSI interfac

Re: [PERFORM] RAID stripe size question

2006-07-18 Thread Ron Peacetree
>From: Alex Turner <[EMAIL PROTECTED]> >Sent: Jul 18, 2006 12:21 AM >To: Ron Peacetree <[EMAIL PROTECTED]> >Cc: Mikael Carneholm <[EMAIL PROTECTED]>, pgsql-performance@postgresql.org >Subject: Re: [PERFORM] RAID stripe size question > >On 7/17/06,

Re: [PERFORM] RAID stripe size question

2006-07-17 Thread Alex Turner
On 7/17/06, Ron Peacetree <[EMAIL PROTECTED]> wrote: -Original Message->From: Mikael Carneholm <[EMAIL PROTECTED]>>Sent: Jul 17, 2006 5:16 PM>To: Ron  Peacetree < [EMAIL PROTECTED]>, pgsql-performance@postgresql.org>Subject: RE: [PERFORM] RAID stripe size q

Re: [PERFORM] RAID stripe size question

2006-07-17 Thread Ron Peacetree
-Original Message- >From: Mikael Carneholm <[EMAIL PROTECTED]> >Sent: Jul 17, 2006 5:16 PM >To: Ron Peacetree <[EMAIL PROTECTED]>, pgsql-performance@postgresql.org >Subject: RE: [PERFORM] RAID stripe size question > >>15Krpm HDs will have average access

Re: [PERFORM] RAID stripe size question

2006-07-17 Thread Mark Kirkwood
Mikael Carneholm wrote: Btw, here's the bonnie++ results from two different array sets (10+18, 4+24) on the MSA1500: LUN: DATA, 24 disks, stripe size 64K - Version 1.03 --Sequential Output-- --Sequential Input- --Random- -P

Re: [PERFORM] RAID stripe size question

2006-07-17 Thread Mikael Carneholm
>Unless I'm missing something, the only FC or SCSI HDs of ~147GB capacity are >15K, not 10K. In the spec we got from HP, they are listed as model 286716-B22 (http://www.dealtime.com/xPF-Compaq_HP_146_8_GB_286716_B22) which seems to run at 10K. Don't know how old those are, but that's what we go

Re: [PERFORM] RAID stripe size question

2006-07-17 Thread Alex Turner
On 7/17/06, Mikael Carneholm <[EMAIL PROTECTED]> wrote: >> This is something I'd also would like to test, as a common>> best-practice these days is to go for a SAME (stripe all, mirroreverything) setup.>> From a development perspective it's easier to use SAME as the >> developers won't have to thin

Re: [PERFORM] RAID stripe size question

2006-07-17 Thread Steinar H. Gunderson
On Mon, Jul 17, 2006 at 09:40:30AM -0400, Ron Peacetree wrote: > Unless I'm missing something, the only FC or SCSI HDs of ~147GB capacity are > 15K, not 10K. > (unless they are old?) There are still 146GB SCSI 1rpm disks being sold here, at least. /* Steinar */ -- Homepage: http://www.sesse

Re: [PERFORM] RAID stripe size question

2006-07-17 Thread Ron Peacetree
>From: Mikael Carneholm <[EMAIL PROTECTED]> >Sent: Jul 16, 2006 6:52 PM >To: pgsql-performance@postgresql.org >Subject: [PERFORM] RAID stripe size question > >I have finally gotten my hands on the MSA1500 that we ordered some time >ago. It has 28 x 10K 146Gb drives, > Unless I'm missing something,

Re: [PERFORM] RAID stripe size question

2006-07-17 Thread Mikael Carneholm
>> This is something I'd also would like to test, as a common >> best-practice these days is to go for a SAME (stripe all, mirror everything) setup. >> From a development perspective it's easier to use SAME as the >> developers won't have to think about physical location for new >> tables/indice

Re: [PERFORM] RAID stripe size question

2006-07-17 Thread Markus Schaber
Hi, Mikael, Mikael Carneholm wrote: > This is something I'd also would like to test, as a common best-practice > these days is to go for a SAME (stripe all, mirror everything) setup. > From a development perspective it's easier to use SAME as the developers > won't have to think about physical lo

Re: [PERFORM] RAID stripe size question

2006-07-17 Thread Mikael Carneholm
>I think the main difference is that the WAL activity is mostly linear, where the normal data activity is rather random access. That was what I was expecting, and after reading http://www.pcguide.com/ref/hdd/perf/raid/concepts/perfStripe-c.html I figured that a different stripe size for the WAL s

Re: [PERFORM] RAID stripe size question

2006-07-17 Thread Markus Schaber
Hi, Mikael, Mikael Carneholm wrote: > An 0+1 array of 4 disks *could* be enough, but I'm still unsure how WAL > activity correlates to "normal data" activity (is it 1:1, 1:2, 1:4, > ...?) I think the main difference is that the WAL activity is mostly linear, where the normal data activity is rat

Re: [PERFORM] RAID stripe size question

2006-07-17 Thread Mikael Carneholm
-Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Michael Stone Sent: den 17 juli 2006 02:04 To: pgsql-performance@postgresql.org Subject: Re: [PERFORM] RAID stripe size question On Mon, Jul 17, 2006 at 12:52:17AM +0200, Mikael Carneholm wrote: >I have final

Re: [PERFORM] RAID stripe size question

2006-07-16 Thread Alex Turner
With 18 disks dedicated to  data, you could make 100/7*9 seeks/second (7ms av seeks time, 9 independant units) which is 128seeks/second writing on average 64kb of data, which is 4.1MB/sec throughput worst case, probably 10x best case so 40Mb/sec - you might want to take more disks for your data and

Re: [PERFORM] RAID stripe size question

2006-07-16 Thread Michael Stone
On Mon, Jul 17, 2006 at 12:52:17AM +0200, Mikael Carneholm wrote: I have finally gotten my hands on the MSA1500 that we ordered some time ago. It has 28 x 10K 146Gb drives, currently grouped as 10 (for wal) + 18 (for data). There's only one controller (an emulex), but I hope You've got 1.4TB as

Re: [PERFORM] RAID stripe size question

2006-07-16 Thread Steinar H. Gunderson
On Mon, Jul 17, 2006 at 12:52:17AM +0200, Mikael Carneholm wrote: > Now to the interesting part: would it make sense to use different stripe > sizes on the separate disk arrays? In theory, a smaller stripe size > (8-32K) should increase sequential write throughput at the cost of > decreased positio

Re: [PERFORM] RAID Stripe size

2005-09-20 Thread evgeny gridasov
We have a production server(8.0.2) running 24x7, 300k+ transactions per day. Linux 2.6.11 / JFS file system. No problems. It works faster than ext3. > Alex Turner wrote: > > > I would also recommend looking at file system. For us JFS worked > > signifcantly > > faster than resier for large r

Re: [PERFORM] RAID Stripe size

2005-09-20 Thread Alex Turner
I have found JFS to be just fine.  We have been running a medium load on this server for 9 months with no unscheduled down time.  Datbase is about 30gig on disk, and we get about 3-4 requests per second that generate results sets in the thousands from about 8am to about 11pm. I have foudn that JFS

Re: [PERFORM] RAID Stripe size

2005-09-20 Thread Welty, Richard
Alex Turner wrote: > I would also recommend looking at file system. For us JFS worked > signifcantly > faster than resier for large read loads and large write loads, so we chose > JFS > over ext3 and reiser. has jfs been reliable for you? there seems to be a lot of conjecture about inst

Re: [PERFORM] RAID Stripe size

2005-09-20 Thread Alex Turner
I have benched different sripe sizes with different file systems, and the perfmance differences can be quite dramatic. Theoreticaly a smaller stripe is better for OLTP as you can write more small transactions independantly to more different disks more often than not, but a large stripe size is goo

Re: [PERFORM] RAID Stripe size

2005-09-20 Thread Jignesh K. Shah
Typically your stripe size impacts read and write. In Solaris, the trick is to match it with your maxcontig parameter. If you set maxcontig to 128 pages which is 128* 8 = 1024k (1M) then your optimal stripe size is 128 * 8 / (number of spindles in LUN).. Assuming number of spindles is 6 then y

Re: [PERFORM] RAID Stripe size

2005-09-20 Thread evgeny gridasov
Hi Everybody! I've got a spare machine which is 2xXEON 3.2GHz, 4Gb RAM 14x140Gb SCSI 10k (LSI MegaRaid 320U). It is going into production in 3-5months. I do have free time to run tests on this machine, and I could test different stripe sizes if somebody prepares a test script and data for that.

Re: [PERFORM] RAID Stripe size

2005-09-20 Thread Michael Stone
On Tue, Sep 20, 2005 at 10:51:41AM +0300, Michael Ben-Nes wrote: I must admit im a bit amazed how such important parameter is so ambiguous. an optimal strip size can improve the performance of the db significantly. It's configuration dependent. IME, it has an insignificant effect. If anything

Re: [PERFORM] RAID Stripe size

2005-09-20 Thread Michael Ben-Nes
Hi John A Meinel wrote: bm\mbn wrote: Hi Everyone The machine is IBM x345 with ServeRAID 6i 128mb cache and 6 SCSI 15k disks. 2 disks are in RAID1 and hold the OS, SWAP & pg_xlog 4 disks are in RAID10 and hold the Cluster itself. the DB will have two major tables 1 with 10 million rows

Re: [PERFORM] RAID Stripe size

2005-09-19 Thread John A Meinel
bm\mbn wrote: > Hi Everyone > > The machine is IBM x345 with ServeRAID 6i 128mb cache and 6 SCSI 15k > disks. > > 2 disks are in RAID1 and hold the OS, SWAP & pg_xlog > 4 disks are in RAID10 and hold the Cluster itself. > > the DB will have two major tables 1 with 10 million rows and one with > 100