Koichi Suzuki wrote:
> Pg_readahead is a tool to prefetch data pages before redoing, based on
> the contents of archive/active WAL segment. For 8.3 and 8.4 without
> sync.rep, this works together with restore_command. Pg_readahead
> analyze WAL segment, schedule and issue posix_fadvise() to prefetch
> data pages quickly before redoing.
>
> Discussions and materials will be found at
>
> http://archives.postgresql.org/pgsql-hackers/2008-10/msg01372.php
>
> So far, external command implemantation speeds up PITR up to six
> times! Therefore, overall recovery time can be a little longer than
> that with FPW.
Now that 8.4 is using fsync, sounds like something that should be
integrated into the core code, rather than as a /contrib.
-- Bruce Momjian <bruce@momjian.us> http://momjian.us EnterpriseDB
http://enterprisedb.com
+ If your life is a hard drive, Christ can be your backup. +