Hi, thanks for all replys. I've done a few tests. Remounting the fs where $PGDATA lives with "forcedirectio" (together with logging, that is default) did not help (if not harm...) performance. Doing what http://blogs.sun.com/roller/page/jkshah suggests: wal_sync_method = fsync (unchanged) wal_buffers = 128 (was 8) checkpoint_segments = 128 (was 3) bgwriter_all_percent = 0 (was 0.333) bgwriter_all_maxpages = 0 (was 5) and leaving everything else default (solarispackages from pgfoundry) increased performance ~ 7 times! Playing around with these modifications I find that it's actually just the wal_buffers = 128 alone which makes all the difference! Quickly playing around with wal_buffers on Linux and Mac OS X I see it influences the performance of my test a bit, maybe in the 10-20% range (I'm really doing quick tests, nothing systematic), but nowhere near as spectacularly as on Solaris. I'm happy so far, but I find it very surprising that this single parameter has such an impact (only on) Solaris 10. (my test program is a bulk inserts using PQputCopyData in large transactions - all test were 8.1.3). Bye, Chris
