| From: | "Sander Steffann" <s(dot)steffann(at)computel(dot)nl> |
|---|---|
| To: | "'Phoenix Kiula'" <phoenix(dot)kiula(at)gmail(dot)com>, "'Bill Moran'" <wmoran(at)potentialtech(dot)com> |
| Cc: | 'Filip Rembiałkowski' <plk(dot)zuber(at)gmail(dot)com>, "'Joshua D(dot) Drake'" <jd(at)commandprompt(dot)com>, <pgsql-general(at)postgresql(dot)org> |
| Subject: | Re: For index bloat: VACUUM ANALYZE vs REINDEX/CLUSTER |
| Date: | 2007-09-18 12:47:43 |
| Message-ID: | 006c01c7f9f2$1b4a1430$51de3c90$@steffann@computel.nl |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-general |
Hi,
> Can I add SHM with merely by managing the entry in sysctl.conf? My
> current values:
>
> kernel.shmmax = 536870912
> kernel.shmall = 536870912
>
> My "shared_buffers" in postgresql.conf is "20000". From the website
> http://www.desknow.com/kb/idx/12/061/article/ I notice that shmmax
> should be sharedbuffer*8192, so I suppose my shmmax can be much lower
> than the above, but I raised it for performance. Am I wrong to do so?
You need to configure the kernel so it allows processes to use more shared
memory. This does not mean that a process automatically uses it. For
PostgreSQL you will need to increase shared_buffers to make it use the extra
available shared memory. With your shared memory settings you can probably
increase shared_buffers to about 65000.
With the 'ipcs' command you can see how much shared memory PostgreSQL uses.
Look under 'Shared Memory Segments' to memory owned by user postgres.
- Sander
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Ron Johnson | 2007-09-18 12:49:59 | Re: Recall: August Monthly techdata split fi |
| Previous Message | Devrim GÜNDÜZ | 2007-09-18 12:42:09 | New PostgreSQL RPM sets are available for Fedora / RHEL |