Re: [HACKERS] Speed up Clog Access by increasing CLOG buffers - Mailing list pgsql-hackers

From Robert Haas
Subject Re: [HACKERS] Speed up Clog Access by increasing CLOG buffers
Date
Msg-id CA+TgmoYKqjN79SpLKWC8kq0gJti1V7MmbG5GZ+arkbGHrKnVow@mail.gmail.com
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In response to Re: [HACKERS] Speed up Clog Access by increasing CLOG buffers  (Robert Haas <robertmhaas@gmail.com>)
List pgsql-hackers
On Thu, Mar 9, 2017 at 5:49 PM, Robert Haas <robertmhaas@gmail.com> wrote:
> However, I just realized that in
> both this case and in the case of group XID clearing, we weren't
> advertising a wait event for the PGSemaphoreLock calls that are part
> of the group locking machinery.  I think we should fix that, because a
> quick test shows that can happen fairly often -- not, I think, as
> often as we would have seen LWLock waits without these patches, but
> often enough that you'll want to know.  Patch attached.

I've pushed the portion of this that relates to ProcArrayLock.  (I
know this hasn't been discussed much, but there doesn't really seem to
be any reason for anybody to object, and looking at just the
LWLock/ProcArrayLock wait events gives a highly misleading answer.)

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company



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