Hi, I try postgresql V 7.1.2 under solaris 2.8 ( patch + the last version ) and i use directio implementation for ufs . Improved UFS Direct I/O Concurrency (Quick I/O Equivalent) Solaris 8 1/01 update release allows concurrent read and write access to regular UFS files. As databases generally pre-allocate files and seldom extend them thereafter, the effects of this enhancement are seen during the normal database operations. The improvement brings I/O-bound database performance on a UFS file system to about 90% of raw partition access speeds. When you mount an ufs partition, just try this command in order to test directio: mount -F ufs -o forcedirectio /dev/dsk/XXX /testdb I try on the same machine 2 databases location : One under partition with directio One under normal ufs partition I use the same postgresql.conf and with pgbench i obtain this resulats: Pgbench -c 4 -v -t 100 testdb ( directio ufs ) tps = 13.425330 tps = 13.626090 Pgbench -c 4 -v -t 100 testdb ( ufs ) tps = 30.052012 tps = 30.630632 If you interest with directio try this links : http://gecitsolutions.systemnews.com/system-news/jobdir/submitted/2001.03/3076/3076.html http://www.idg.net/crd_solaris_452714_102.html Cheers, PEJAC Pascal ---------------------------(end of broadcast)--------------------------- TIP 5: Have you checked our extensive FAQ? http://www.postgresql.org/users-lounge/docs/faq.html
