Re: Configuring Shared Buffers

Yes, I was talking about 100 max connections...
I am doing some benchmarks tests with diferent configurations...
I'll try what you said Kevin.

Thank you All

2008/6/30 Kevin Neufeld <kneufeld(at)refractions(dot)net>:

> I agree. I have a similar system that I use for development purposes and
> have the shared_buffers sitting comfortable around 1GB. On production
> systems with 16GB of RAM, I've seen this as high as 12GB. There is talk
> nowadays, however, that this setting could drop back down to defaults on
> modern installations and let the OS handle cached memory as it sees fit.
> In any case, the biggest performance gain I see for you would be setting
> work_mem appropriately. This is the memory postgres is permitted to use for
> sorts, merges, hash joins, etc. before being forced to disk. It defaults
> to 1MB. In my opinion, this is far too low. This is the memory allocated
> to each sort/hash/etc operation. So for a complicated query, postgres could
> use several allocations. Even though, I think you could raise this
> considerably. If your system is a dedicated postgres box, I would take the
> total memory, subtract that needed for the OS, subtract what you decided to
> use for shared_buffers, and divide the rest by your 100 connections. So,
> for you, I see this around 30MB. On my development box with only a few
> connections, I have this around 500MB and sometime spike it to 1.2GB on the
> fly before a long running query.
>
> Cheers,
> Kevin
>
> Alvaro Herrera wrote:
>
>> Rafael Domiciano escribió:
>>
>>
>>> The Postgres version is 8.3.3 and I am using Fedora Core 8.
>>> I have in the actual server around 70 connections the same time. I am
>>> assigning for this 100.
>>>
>>>
>>
>> 100 MB? That's not very much either. You can probably get a hefty
>> performance boost by upping it a lot more (depending on whether the
>> machine is doing something else, or Postgres is the only service running
>> on it.)
>>
>>
>>
>>
>
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