I wanted to follow up from this question. I’m running on 9.3.4
My DB server has 32GB ram so I have assigned 8GB shared_buffer_memory. It
is quite a big db but with not much traffic. When there is traffic, it’s usually
big.
Lately, the kernel has been killing the postmaster for having assigned too
much shared memory. Latest crash was when loading a 500MB file.
Should I reduce the shared buffers in order for this to be more
robust?
Thanks
Markella
Sent: Wednesday, March 26, 2014 12:45 PM
Subject: Re: Why shared_buffers max is
8GB?
Il 26/mar/2014 13:36 "Ilya Kosmodemiansky" <ilya.kosmodemiansky@xxxxxxxxxxxxxxxxxxxxxxxxx>
ha scritto:
>
> Hi Alexey,
>
> On Wed, Mar 26, 2014 at
1:21 PM, Alexey Vasiliev <leopard_ne@xxxxxxxx> wrote:
>
> I read from several sources, what maximum shared_buffers is
8GB.
>
> I believe that was an issue on some older versions, and
thats why was
> mentioned in several talks. Today it is a sort of
apocrypha.
>
> > Does this true? If yes, why exactly this number
is maximum number of
> > shared_buffers for good performance (on Linux
64-bits)?
>
> 25% of available RAM is a good idea to start.
Sometimes, if you have
> heavy workload _and_ it is possible to reside
whole database in
> memory, better to use something larger, about
~75% of RAM.
>
> Best regards,
> Ilya
> --
> Ilya
Kosmodemiansky,
>
> PostgreSQL-Consulting.com
> tel.
+14084142500
> cell. +4915144336040
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>
>
>
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max is 1024mb.
you have to test your workload if it's too low you will get too much
i/o ( the filesystem cache could help.. not always /*nfs*/), if too high
your cpu will be eated by lru/ latch/ and so on.
Mat Dba
