From: Alex Turner <armtuk@gmail.com>
To: Alan Stange <stange@rentec.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Performance on SUSE w/ reiserfs
Date: Tue, 11 Oct 2005 14:11:02 -0400
Message-ID: <33c6269f0510111111i676a2e50h57cd06757c59a3da@mail.gmail.com> (raw)
In-Reply-To: <434BDA1E.5030804@rentec.com>
References: <434ADD46.5060206@npcinternational.com>
<6247.1128981289@sss.pgh.pa.us>
<434AE7FF.4000705@npcinternational.com>
<33c6269f0510110727q62a797a1g9493661e1dc905d4@mail.gmail.com>
<434BD17E.7000605@rentec.com>
<33c6269f0510110757v1632b9c5te578b699db922f45@mail.gmail.com>
<434BDA1E.5030804@rentec.com>
Well - to each his own I guess - we did extensive testing on 1.4, and it
refused to allocate much past 1gig on both Linux x86/x86-64 and Windows.
Alex
On 10/11/05, Alan Stange <stange@rentec.com> wrote:
>
> Alex Turner wrote:
>
> > Perhaps this is true for 1.5 on x86-32 (I've only used it on x86-64)
> > but I was more thinking 1.4 which many folks are still using.
>
> The 1.4.x JVM's will also work just fine with much more than 1GB of
> memory. Perhaps you'd like to try again?
>
> -- Alan
>
> >
> > On 10/11/05, *Alan Stange* <stange@rentec.com
> > <mailto:stange@rentec.com>> wrote:
> >
> > Alex Turner wrote:
> >
> > > Realise also that unless you are running the 1.5 x86-64 build, java
> > > will not use more than 1Gig, and if the app server requests more
> > than
> > > 1gig, Java will die (I've been there) with an out of memory error,
> > > even though there is plenty of free mem available. This can
> > easily be
> > > cause by a lazy GC thread if the applicaiton is running high on
> > CPU usage.
> >
> > On my side of Planet Earth, the standard non-x64 1.5 JVM will happily
> > use more than 1G of memory (on linux and Solaris, can't speak for
> > Windows). If you're running larger programs, it's probably a good
> > idea
> > to use the -server compiler in the JVM as well. I regularly run with
> > -Xmx1800m and regularly have >1GB heap sizes.
> >
> > The standard GC will not cause on OOM error if space remains for the
> > requested object. The GC thread blocks all other threads during its
> > activity, whatever else is happening on the machine. The
> > newer/experimental GC's did have some potential race conditions, but I
> > believe those have been resolved in the 1.5 JVMs.
> >
> > Finally, note that the latest _05 release of the 1.5 JVM also now
> > supports large page sizes on Linux and Windows:
> > -XX:+UseLargePages this can be quite beneficial depending on the
> > memory patterns in your programs.
> >
> > -- Alan
> >
> >
>
>
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-performance@postgresql.org
Cc: armtuk@gmail.com, stange@rentec.com
Subject: Re: Performance on SUSE w/ reiserfs
In-Reply-To: <33c6269f0510111111i676a2e50h57cd06757c59a3da@mail.gmail.com>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox