Re: PostgreSQL win32 fragmentation issue

Magnus Hagander <mha@sollentuna.net>

From: "Magnus Hagander" <mha@sollentuna.net>
To: "Thomas H." <me@alternize.com>, "Matthew T. O'Connor" <matthew@zeut.net>, "Martijn van Oosterhout" <kleptog@svana.org>
Cc: "Joshua D. Drake" <jd@commandprompt.com>, "PostgreSQL-development" <pgsql-hackers@postgresql.org>
Date: 2006-12-02T20:21:26Z
Lists: pgsql-hackers
> >>> I know this isn't *our* fault :) but I am curious if there is 
> >>> anything we can do about the way postgresql writes files to help 
> >>> limit fragmentation.
> >>>
> >>> Essentially, this makes win32 impossible in a 24x7 environment 
> >>> (jokes aside about Win32 in general) because we *have* to 
> defrag on 
> >>> Windows and Windows won't defrag open files (thus 
> anything PostgreSQL is using).
> >>>
> >>
> >> BTW, do you know what 11% fragmentation means? Does that mean each 
> >> file is on average split in 9 pieces, because for a 1GB file, 9 
> >> pieces isn't all that bad.
> 
> in our win32/ntfs environment, only 6 pgsql data-files are 
> fragmented. but they are heavily fragmented. fragmentiation 
> ranges from 1369 fragments for a 14mb file to 4548 fragments 
> for a 628mb one... the database is only 1 week old.

Which relations do these files represent?

//Magnus