Bill Preston <billpreston@xxxxxxxxxxxxxxxx> writes: > I've noticed some performance problems that I am guessing are WAL > related based on my browsing around and wondered if someone had some > suggestions for tuning the WAL settings. It could also help if someone > just laughed at me and told me it wasn't WAL. Consider it done ;-). I'm not sure what your problem is but it's unlikely to be WAL, especially not if you're using the same WAL-related settings in 8.1 and 8.3. Which you might not be. The large speedup from wrapping many small inserts into one transaction is entirely expected and should have occurred on 8.1 as well. I am suspicious that you were running 8.1 with fsync off and 8.3 has it on. Do you still have your 8.1 postgresql.conf? Comparing all the non-defaulted settings would be the first thing to do. If it's not that, I'm not sure. One cross-version difference that comes to mind is that 8.3 is a bit stickier about implicit casting, and so it seems conceivable that something about these queries was considered indexable in 8.1 and is not in 8.3. But you've not provided enough detail to do more than speculate. regards, tom lane -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
