Thread: 64bits or 32 bits on ESX?
We are going to be setting up a PostgreSQL server on a guest under VMWare ESX 4... Is there any performance improvement bychoosing 64bits Linux over 32bits Linux as the guest OS or is it almost the same? Regards, BTJ -- ----------------------------------------------------------------------------------------------- Bjørn T Johansen btj@havleik.no ----------------------------------------------------------------------------------------------- Someone wrote: "I understand that if you play a Windows CD backwards you hear strange Satanic messages" To which someone replied: "It's even worse than that; play it forwards and it installs Windows" -----------------------------------------------------------------------------------------------
2010/1/21 Bjørn T Johansen <btj@havleik.no>: > We are going to be setting up a PostgreSQL server on a guest under VMWare ESX 4... Is there any performance improvementby choosing 64bits Linux over > 32bits Linux as the guest OS or is it almost the same? How much resources do you plan to give the machine? If you're setting up a very constrained machine with little memory, go with the 32-bit version. It'll use slightly less memory which can be important if you're constrained. If you're setting up a medium size or bigger machine (2Gb+ memory), use a 64-bit version. If you plan you may eventually need to increase the size of the machine, go with the 64-bit one from the beginning, because changing from 32 to 64 bit requires dump/reload. -- Magnus Hagander Me: http://www.hagander.net/ Work: http://www.redpill-linpro.com/
On Thu, 21 Jan 2010 10:43:31 +0100 Magnus Hagander <magnus@hagander.net> wrote: > 2010/1/21 Bjørn T Johansen <btj@havleik.no>: > > We are going to be setting up a PostgreSQL server on a guest under VMWare ESX 4... Is there any performance improvementby choosing 64bits Linux > > over 32bits Linux as the guest OS or is it almost the same? > > How much resources do you plan to give the machine? > > If you're setting up a very constrained machine with little memory, go > with the 32-bit version. It'll use slightly less memory which can be > important if you're constrained. > > If you're setting up a medium size or bigger machine (2Gb+ memory), > use a 64-bit version. If you plan you may eventually need to increase > the size of the machine, go with the 64-bit one from the beginning, > because changing from 32 to 64 bit requires dump/reload. > ok... we were thinking about 2GB RAM, so maybe we should try 64bit.... :) BTJ
In response to Magnus Hagander : > 2010/1/21 Bjørn T Johansen <btj@havleik.no>: > > We are going to be setting up a PostgreSQL server on a guest under VMWare ESX 4... Is there any performance improvementby choosing 64bits Linux over > > 32bits Linux as the guest OS or is it almost the same? > > How much resources do you plan to give the machine? > > If you're setting up a very constrained machine with little memory, go > with the 32-bit version. It'll use slightly less memory which can be > important if you're constrained. > > If you're setting up a medium size or bigger machine (2Gb+ memory), > use a 64-bit version. If you plan you may eventually need to increase Really? With ONLY 2Gb? Why? What is the performance improvement, with 64Bit all pointers and so on needs more memory so i'm expecting lesser memory for the data. I'm wrong? Andreas -- Andreas Kretschmer Kontakt: Heynitz: 035242/47150, D1: 0160/7141639 (mehr: -> Header) GnuPG: 0x31720C99, 1006 CCB4 A326 1D42 6431 2EB0 389D 1DC2 3172 0C99
On Thu, Jan 21, 2010 at 12:45, A. Kretschmer <andreas.kretschmer@schollglas.com> wrote: > In response to Magnus Hagander : >> 2010/1/21 Bjørn T Johansen <btj@havleik.no>: >> > We are going to be setting up a PostgreSQL server on a guest under VMWare ESX 4... Is there any performance improvementby choosing 64bits Linux over >> > 32bits Linux as the guest OS or is it almost the same? >> >> How much resources do you plan to give the machine? >> >> If you're setting up a very constrained machine with little memory, go >> with the 32-bit version. It'll use slightly less memory which can be >> important if you're constrained. >> >> If you're setting up a medium size or bigger machine (2Gb+ memory), >> use a 64-bit version. If you plan you may eventually need to increase > > Really? With ONLY 2Gb? Why? What is the performance improvement, with > 64Bit all pointers and so on needs more memory so i'm expecting lesser > memory for the data. > > I'm wrong? While the theoretical limit is a bit higher, the fact that you have to reinstall once you've realized you wanted to add a little bit more memory.... More important to me at least :-) -- Magnus Hagander Me: http://www.hagander.net/ Work: http://www.redpill-linpro.com/
On Thu, 21 Jan 2010 13:01:29 +0100 Magnus Hagander <magnus@hagander.net> wrote: > On Thu, Jan 21, 2010 at 12:45, A. Kretschmer > <andreas.kretschmer@schollglas.com> wrote: > > In response to Magnus Hagander : > >> 2010/1/21 Bjørn T Johansen <btj@havleik.no>: > >> > We are going to be setting up a PostgreSQL server on a guest under VMWare ESX 4... Is there any performance improvementby choosing 64bits > >> > Linux over 32bits Linux as the guest OS or is it almost the same? > >> > >> How much resources do you plan to give the machine? > >> > >> If you're setting up a very constrained machine with little memory, go > >> with the 32-bit version. It'll use slightly less memory which can be > >> important if you're constrained. > >> > >> If you're setting up a medium size or bigger machine (2Gb+ memory), > >> use a 64-bit version. If you plan you may eventually need to increase > > > > Really? With ONLY 2Gb? Why? What is the performance improvement, with > > 64Bit all pointers and so on needs more memory so i'm expecting lesser > > memory for the data. > > > > I'm wrong? > > While the theoretical limit is a bit higher, the fact that you have to > reinstall once you've realized you wanted to add a little bit more > memory.... More important to me at least :-) > I also thought that the fact the 64bit system can move more data in parallell would also make the system faster.... BTJ
2010/1/21 Bjørn T Johansen <btj@havleik.no>: > I also thought that the fact the 64bit system can move more data in parallell would also make the system faster.... That's true ad the chip level (registers and cache). Anything else depends on the surrounding hardware (design and implementation). A 32bit system with a good SAS subsystem can outperform a 64bit one with poor PATA disks. -- Vincenzo Romano NotOrAnd Information Technologies NON QVIETIS MARIBVS NAVTA PERITVS
On Thursday 21 January 2010 13.01:29 Magnus Hagander wrote: > > Really? With ONLY 2Gb? Why? What is the performance improvement, with > > 64Bit all pointers and so on needs more memory so i'm expecting lesser > > memory for the data. > I'm not in any way a performance expert, but IIRC 32 bit Linux has to use some quirky logic (HIGHMEM) to address more than 2G physical memory, which might reduce performance somewhat. So 2G is fine, but ... Aside of memory: if performance is an issue, and assuming your db is bigger than available memory: have you thought about the physical disk layout? Having indices on different disks (physical disks matter, here!) from data, splitting WAL from tablespaces etc. might all be much more important for your performance than the 32bit vs. 64bit issue. cheers -- vbi
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I have seen no difference in performance. Now, if you want large memory for a DB server, and you should, 64 is the way to go. I'm currently running CentOS 5 64-Bit vm's for the SaaS app I support. Works great on ESX 4U1. -- Larry Rosenman http://www.lerctr.org/~ler Phone: +1 512-248-2683 E-Mail: ler@lerctr.org US Mail: 430 Valona Loop, Round Rock, TX 78681-3893 -----Original Message----- From: pgsql-general-owner@postgresql.org [mailto:pgsql-general-owner@postgresql.org] On Behalf Of Bjørn T Johansen Sent: Thursday, January 21, 2010 1:07 AM To: pgsql-general@postgresql.org Subject: [GENERAL] 64bits or 32 bits on ESX? We are going to be setting up a PostgreSQL server on a guest under VMWare ESX 4... Is there any performance improvement by choosing 64bits Linux over 32bits Linux as the guest OS or is it almost the same? Regards, BTJ -- ---------------------------------------------------------------------------- ------------------- Bjørn T Johansen btj@havleik.no ---------------------------------------------------------------------------- ------------------- Someone wrote: "I understand that if you play a Windows CD backwards you hear strange Satanic messages" To which someone replied: "It's even worse than that; play it forwards and it installs Windows" ---------------------------------------------------------------------------- ------------------- -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
On Thu, 21 Jan 2010 13:01:29 +0100 Magnus Hagander <magnus@hagander.net> wrote: > On Thu, Jan 21, 2010 at 12:45, A. Kretschmer > <andreas.kretschmer@schollglas.com> wrote: > > In response to Magnus Hagander : > >> 2010/1/21 Bjørn T Johansen <btj@havleik.no>: > >> > We are going to be setting up a PostgreSQL server on a guest under VMWare ESX 4... Is there any performance improvementby choosing 64bits > >> > Linux over 32bits Linux as the guest OS or is it almost the same? > >> > >> How much resources do you plan to give the machine? > >> > >> If you're setting up a very constrained machine with little memory, go > >> with the 32-bit version. It'll use slightly less memory which can be > >> important if you're constrained. > >> > >> If you're setting up a medium size or bigger machine (2Gb+ memory), > >> use a 64-bit version. If you plan you may eventually need to increase > > > > Really? With ONLY 2Gb? Why? What is the performance improvement, with > > 64Bit all pointers and so on needs more memory so i'm expecting lesser > > memory for the data. > > > > I'm wrong? > > While the theoretical limit is a bit higher, the fact that you have to > reinstall once you've realized you wanted to add a little bit more > memory.... More important to me at least :-) > I also thought that the fact the 64bit system can move more data in parallell would also make the system faster.... BTJ