Re: AIX 5.3 Out of Memory Error - 64-bit

On Fri, 2009-12-11 at 11:18 -0700, Scott Marlowe wrote:
> On Fri, Dec 11, 2009 at 6:40 AM, Thorne, Francis <thornef(at)cromwell(dot)co(dot)uk> wrote:
> > Hi All
> >
> > I'm looking for some help with regards a postgres 64-bit install I set up
> > on a IBM AIX machine.
> >
> > I used the following install options whien I installed postgres
> >
> > BINDIR =
> > /usr/local/pgsql837-64/bin
> > DOCDIR =
> > /usr/local/pgsql837-64/doc
> > INCLUDEDIR =
> > /usr/local/pgsql837-64/include
> > PKGINCLUDEDIR =
> > /usr/local/pgsql837-64/include
> > INCLUDEDIR-SERVER =
> > /usr/local/pgsql837-64/include/server
> > LIBDIR =
> > /usr/local/pgsql837-64/lib
> > PKGLIBDIR =
> > /usr/local/pgsql837-64/lib
> > LOCALEDIR
> > =
> > MANDIR =
> > /usr/local/pgsql837-64/man
> > SHAREDIR =
> > /usr/local/pgsql837-64/share
> > SYSCONFDIR =
> > /usr/local/pgsql837-64/etc
> > PGXS =
> > /usr/local/pgsql837-64/lib/pgxs/src/makefiles/pgxs.mk
> > CONFIGURE = '--prefix=/usr/local/pgsql837-64' '--with-pgport=5422'
> > '--enable-thr
> > ead-safety' '--enable-integer-datetimes' 'CC=gcc -maix64'
> > 'LDFLAGS=-Wl,-bbigtoc'
> > CC = gcc
> > -maix64
> > CPPFLAGS
> > =
> > CFLAGS = -O2 -Wall -Wmissing-prototypes -Wpointer-arith -Winline
> > -Wdeclaration-a
> > fter-statement -Wendif-labels -fno-strict-aliasing
> > -fwrapv
> > CFLAGS_SL
> > =
> > LDFLAGS = -Wl,-bbigtoc
> > -Wl,-blibpath:/usr/local/pgsql837-64/lib:/usr/lib:/lib
> > LDFLAGS_SL = -Wl,-bnoentry -Wl,-H512
> > -Wl,-bM:SRE
> > LIBS = -lpgport -lz -lreadline -lld
> > -lm
> > VERSION = PostgreSQL 8.3.7
> >
> > And the spec of the AIX machine is a follows.
> >
> > AIX 5.3
> > 2x Power 5 CPU's
> > 6GB RAM
> >
> > If I run postgres with the standard postgresql.conf install then all queries
> > run (albiet sometimes slower than i'd expect). However if I start to change
> > some of the memory settings for example shared_buffers, temp_buffers,
> > work_mem, maintenance_workmem above 128-256MB and run a large query or
> > create a large indexes i get the error below
> >
> > Out of Memory
> > Failed on request of size 167873 (this value will change)
> >
> > Any thoughts or ideas would be greatly appreciated
>
> Don't set work_mem so high? shared_buffers at 256M is no big deal.
> work_mem at 256M is per sort. So a dozen users each running queries
> with 3 or 4 sorts could chew up 6G pretty fast.

AIX also sets a 2GB limit per process by default - security policy I
believe (not 100% sure of the exact details). I've hit this on 64bit
AIX 5.3.

--
Brad Nicholson 416-673-4106
Database Administrator, Afilias Canada Corp.