On Tue, Dec 21, 2010 at 4:49 AM, Robert Haas <robertmh...@gmail.com> wrote: > On Sun, Dec 19, 2010 at 1:10 PM, Jim Nasby <j...@nasby.net> wrote: >> On Dec 19, 2010, at 1:10 AM, flyusa2010 fly wrote: >>> Does postgres make an effort to create a file with physically continuous >>> blocks? >> >> AFAIK all files are expanded as needed. I don't think there's any flags you >> can pass to the filesystem to tell it "this file will eventually be 1GB in >> size". So, we're basically at the mercy of the FS to try and keep things >> contiguous. > > There have been some reports that we would do better on some > filesystems if we extended the file more than a block at a time, as we > do today. However, AFAIK, no one is pursuing this ATM. >
The has been found to be the case in the MySQL world, particularly when ext3 is in use: http://forge.mysql.com/worklog/task.php?id=4925 http://www.facebook.com/note.php?note_id=194501560932 Also, InnoDB has an option for how much data should be allocated at the end of a tablespace when it needs to grow: http://dev.mysql.com/doc/refman/5.0/en/innodb-parameters.html#sysvar_innodb_data_file_path -- Rob Wultsch wult...@gmail.com -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
