Re: [HACKERS] Parallel Select query performance and shared buffers

[Metin Doslu <metin@xxxxxxxxxxxxx>]

> You could try my lwlock-scalability improvement patches - for some
> workloads here, the improvements have been rather noticeable. Which
> version are you testing?

I tried your patches on next link. As you suspect I didn't see any improvements. I tested it on PostgreSQL 9.2 Stable.

http://git.postgresql.org/gitweb/?p=users/andresfreund/postgres.git;a=shortlog;h=refs/heads/REL9_2_STABLE-rwlock-contention

On Wed, Dec 4, 2013 at 8:26 PM, Andres Freund <andres@xxxxxxxxxxxxxxx> wrote:

On 2013-12-04 20:19:55 +0200, Metin Doslu wrote:
> - When we increased NUM_BUFFER_PARTITIONS to 1024, this problem is
> disappeared for 8 core machines and come back with 16 core machines on
> Amazon EC2. Would it be related with PostgreSQL locking mechanism?

You could try my lwlock-scalability improvement patches - for some
workloads here, the improvements have been rather noticeable. Which
version are you testing?

Greetings,

Andres Freund

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