Horton

Re: LWLOCK_STATS

Tom Lane <tgl@sss.pgh.pa.us>

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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>
Cc: Robert Haas <robertmhaas@gmail.com>, pgsql-hackers@postgresql.org
Date: 2012-01-07T17:18:23Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Take fewer snapshots.

  2. Various micro-optimizations for GetSnapshopData().

Heikki Linnakangas <heikki.linnakangas@enterprisedb.com> writes:
> A couple of weeks ago I wrote a little patch that's similar to 
> LWLOCK_STATS, but it prints out % of wallclock time that is spent 
> acquiring, releasing, or waiting for a lock. I find that more useful 
> than the counters.

I would think that the measurement overhead required to obtain two
wall-clock values for every LWLock touch would be so high as to render
any results from this quite suspect.

			regards, tom lane