2011/6/1 Tatsuo Ishii <is...@postgresql.org>: >> Yeah, I'm pretty well convinced this whole approach is a dead end. >> Priming the OS buffer cache seems way more useful. I also think >> saving the blocks to be read rather than the actual blocks makes a lot >> more sense. > > Well, his proposal works on any platforms PostgreSQL supports. On the > other hand PgFincore works on Linux only. Who wants Linux only tool be > in core?
I don't want to compete the features here. Just for the completeness: PgFincore 'snapshot' is possible on any platform supporting mincure() (most support it, for widows alternatives exists). For restoring, it can be a ReadBuffer for postgresql cache; for OS it can be an open(),read(X), read (Y), close() *or* posix_fadvise() which can be less destructive (I did only via posix_fadv but nothing prevent to change that when posix support is not present). And we already have linux-only feature in-core, fortunately because it is usefull feature and I really like to add more posix_fadvise call (*this* will really help read and cache strategy more than any hack we can do to try to workaround kernel decisions) Note that BSD developers can change that and make posix_fadvise work: it has been sitting in their TODO list since some years now. Anyway we need this patch on-list to go ahead. > > Also I really want to see the performance comparison between these two > approaches in the real world database. > -- > Tatsuo Ishii > SRA OSS, Inc. Japan > English: http://www.sraoss.co.jp/index_en.php > Japanese: http://www.sraoss.co.jp > > -- > Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-hackers > -- Cédric Villemain 2ndQuadrant http://2ndQuadrant.fr/ PostgreSQL : Expertise, Formation et Support -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
