Horton

Re: Clock sweep not caching enough B-Tree leaf pages?

Andres Freund <andres@2ndquadrant.com>

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From: Andres Freund <andres@2ndquadrant.com>
To: Peter Geoghegan <pg@heroku.com>
Cc: Greg Stark <stark@mit.edu>, Ants Aasma <ants@cybertec.at>, Pg Hackers <pgsql-hackers@postgresql.org>
Date: 2014-04-17T20:39:20Z
Lists: pgsql-hackers 
On 2014-04-17 13:33:27 -0700, Peter Geoghegan wrote:
> Just over 99.6% of pages (leaving aside the meta page) in the big 10
> GB pgbench_accounts_pkey index are leaf pages.

That's a rather nice number. I knew it was big, but I'd have guessed
it'd be a percent lower.

Do you happen to have the same stat handy for a sensibly wide text or
numeric real world index? It'd be interesting to see what the worst case
there is.

Greetings,

Andres Freund

-- 
 Andres Freund	                   http://www.2ndQuadrant.com/
 PostgreSQL Development, 24x7 Support, Training & Services

Commits

  1. Replace the BufMgrLock with separate locks on the lookup hashtable and