Re: Win32 Backend Cash - pre-existing shared memory block is still in use

From: Magnus Hagander <magnus(at)hagander(dot)net>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: Scott Marlowe <scott(dot)marlowe(at)gmail(dot)com>, Jeremy Palmer <JPalmer(at)linz(dot)govt(dot)nz>, "pgsql-general(at)postgresql(dot)org" <pgsql-general(at)postgresql(dot)org>, Alvaro Herrera <alvherre(at)commandprompt(dot)com>
Subject: Re: Win32 Backend Cash - pre-existing shared memory block is still in use
Date: 2010-08-25 08:10:44
Message-ID: AANLkTinAPh+vdAkJzQFpswzt9vcHrxoJ65Jk0qqZKO+N@mail.gmail.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-general

On Wed, Aug 25, 2010 at 07:34, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> I wrote:
>> Cutting his value for shared_buffers (currently about 800MB) might be
>> wise too.  I'm not sure what the effectively available address space
>> for a win32 process is, but if there's any inefficiency in the way
>> the address space is laid out, those numbers could be enough to be
>> trouble.
>
> Actually, a bit of googling turns up this:
>
> http://msdn.microsoft.com/en-us/library/aa366778(VS.85).aspx
>
> which says that the available userspace address range for a win32
> process is only *two* gig (although you can get to three using tricks
> that I doubt are in his PG build).  Take 800M+500M off the top, and it's

Correct, we don't set ourselves as large address aware.

Hmm. I wonder if we even do that with the 64-bit build. I'm pretty
sure I tried with shared_buffers > 4Gb, but now that i see that page,
I think I need to re-verify that :-)

--
 Magnus Hagander
 Me: http://www.hagander.net/
 Work: http://www.redpill-linpro.com/

In response to

Browse pgsql-general by date

  From Date Subject
Next Message Wappler, Robert 2010-08-25 10:08:45 Re: Feature proposal
Previous Message Craig Ringer 2010-08-25 08:06:09 Re: How to setup PostgreSQL to work with libpam-pgsql/libnss-pgsql2?