On Fri, 10 Oct 2008, Pascal Cohen wrote:
Are there best practices to reduce the migration time ?
There's a number of resources in this area listed at http://wiki.postgresql.org/wiki/Bulk_Loading_and_Restores
I wanted to have an expectation of the migration duration and performed it on a less powerful machine than the one we have in Production.
Note that if your production server has any sort of decent disk controller in it, but the test machine doesn't, you can end up with results that don't extrapolate very well. That's particularly true if you don't follow the standard good practice on the restore (like using the default value for checkpoint_segments). As mentioned in the above, using syncronous commit can help a lot there on some systems.
If you do any restore tests again, try and look at what the bottleneck is on the system using something like vmstat, and make sure you check the database log files (that will tell you if the checkpoint stuff is setup reasonably or not). It's really hard to say whether any of the things you were asking about will be helpful or not without knowing what the limiting factor on your system is. If you're CPU limited for example, you'd want to stay away from compression; if I/O limited that might make sense.
-- * Greg Smith gsmith@xxxxxxxxxxxxx http://www.gregsmith.com Baltimore, MD -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
