Re: PostgreSQL backend process high memory usage issue

On Fri, Apr 8, 2011 at 10:30 AM, Shianmiin <Shianmiin(at)gmail(dot)com> wrote:
>
> Shianmiin wrote:
>>
>> Hi Merlin,
>>
>> I revised the test code with attached files and use pgbench to send the
>> test queries.
>>
>>  http://postgresql.1045698.n5.nabble.com/file/n4290723/dotest dotest
>>  http://postgresql.1045698.n5.nabble.com/file/n4290723/initialize.sql
>> initialize.sql
>>  http://postgresql.1045698.n5.nabble.com/file/n4290723/test.sql test.sql
>>
>> Samuel
>>
>
>
> Just want to put some descriptions on the revised test code:
>
> 1. This test is not a real life testing, it's is specifically designed to
> emphasize the high memory usage issue of PostgreSQL backend process we
> encountered.
> 2. The tests in the dotest file uses pgbench's feature to simulate 20
> concurrent clients sending random queries, which will make the host memory
> usage climb even faster; eventually all 20 concurrent PostgreSQL process
> will all use 1.5 GB (30GB in total). To do the same tests as in the original
> post, we can run
>
> pgbench memoryusagetest -c 1 -j 1 -T180 -f test.sql

are you sure you're actually using that memory? I bet you have
configured around 1.5gb shared buffers. What does 'top' say when this
is happening?

merlin