Re: Best COPY Performance
Worky Workerson <worky.workerson@gmail.com>
From: "Worky Workerson" <worky.workerson@gmail.com>
To: "Jim C. Nasby" <jim@nasby.net>
Cc: pgsql-performance@postgresql.org
Date: 2006-10-31T20:22:11Z
Lists: pgsql-performance
> >I'm guessing the high bursts are checkpoints. Can you check your log > > >files for pg and see if you are getting warnings about checkpoint > > >frequency? You can get some mileage here by increasing wal files. > > > > Nope, nothing in the log. I have set: > > wal_buffers=128 > > checkpoint_segments=128 > > checkpoint_timeout=3000 > > which I thought was rather generous. Perhaps I should set it even > > higher for the loads? > > But depending on your shared_buffer and bgwriter settings (as well as > how much WAL traffic you're generating, you could still end up with big > slugs of work to be done when checkpoints happen. > > If you set checkpoint_warning to 3001, you'll see exactly when > checkpoints are happening, so you can determine if that's an issue. I did that, and I get two log messages, seeing checkpoints happening at 316 and 147 seconds apart on my load of a 1.9 GB file. Is this "an issue"? Thanks!