Horton

Re: Draft release notes complete

Robert Haas <robertmhaas@gmail.com>

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From: Robert Haas <robertmhaas@gmail.com>
To: Jeff Janes <jeff.janes@gmail.com>
Cc: Bruce Momjian <bruce@momjian.us>, Peter Geoghegan <peter@2ndquadrant.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2012-05-12T00:37:58Z
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. Expose track_iotiming information via pg_stat_statements.

  2. Rewrite GiST support code for rangetypes.

  3. Clean up a couple of box gist helper functions.

  4. Replace the "New Linear" GiST split algorithm for boxes and points with a

On Fri, May 11, 2012 at 2:03 PM, Jeff Janes <jeff.janes@gmail.com> wrote:
> On Thu, May 10, 2012 at 10:44 AM, Bruce Momjian <bruce@momjian.us> wrote:
>> On Thu, May 10, 2012 at 01:11:54PM +0100, Peter Geoghegan wrote:
>>
>>> Why can't we call group commit group commit (and for that matter,
>>> index-only scans index-only scans), so that people will understand
>>> that we are now competitive with other RDBMSs in this area? "Improve
>>> performance of WAL writes when multiple transactions commit at the
>>> same time" seems like a pretty bad description, since it doesn't make
>>> any reference to batching of commits.  Also, I don't think that the
>>
>> I didn't call it "group commit" because we have settings we used to
>> regard as group commit:
>
> My understanding of that patch is that is does not cause "group
> commit" to happen, but rather when a group commit does happen
> "naturally" it causes all members of the group to awaken more
> quickly/efficiently than they previously would have.

Right.  It's not a new feature; it's a performance improvement.  We've
had group commit for a long time; it just didn't work very well
before.  And it's not batching the commits better; it's reducing the
lock contention around realizing that the batched commit has happened.

>> I updated the release docs to call the item "group commit" because I now
>> don't see any reference to that term in our docs.
>
> I don't think I'd mention WAL writing at all, and just say that it
> improves the concurrency of locking around group commits.

+1.

-- 
Robert Haas
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