Re: CLOG contention, part 2

Merlin Moncure <mmoncure@gmail.com>

From: Merlin Moncure <mmoncure@gmail.com>

To: Jeff Janes <jeff.janes@gmail.com>

Cc: Simon Riggs <simon@2ndquadrant.com>, Robert Haas <robertmhaas@gmail.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>

Date: 2012-01-27T23:16:57Z

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 →

Call check_keywords.pl in maintainer-check
- 9bf8603c7a91 9.2.0 cited
Make the number of CLOG buffers adaptive, based on shared_buffers.
- 33aaa139e630 9.2.0 cited

On Fri, Jan 27, 2012 at 4:05 PM, Jeff Janes <jeff.janes@gmail.com> wrote:
> Also, I think the general approach is wrong.  The only reason to have
> these pages in shared memory is that we can control access to them to
> prevent write/write and read/write corruption.  Since these pages are
> never written, they don't need to be in shared memory.   Just read
> each page into backend-local memory as it is needed, either
> palloc/pfree each time or using a single reserved block for the
> lifetime of the session.  Let the kernel worry about caching them so
> that the above mentioned reads are cheap.

right -- exactly.  but why stop at one page?

merlin