Next up we looked at the PostgreSQL performance, which does stress the hard disk a fair amount. Since the Ubuntu 8.04.3 LTS release the performance has continued to drop, but there was a small recovery with Ubuntu 9.10. Ubuntu 8.04.3 LTS had 815 transactions per second, which dropped to 723 TPS with Ubuntu 8.10, and then even more severely down to 444 TPS with Ubuntu 9.04, which ran up to 491 TPS in Ubuntu 9.10. Ubuntu 9.10 is still running well behind where PostgreSQL was running with Ubuntu a year and a half ago. The PostgreSQL performance will likely drop even more severely with Ubuntu 10.04 LTS due to an EXT4 file-system change in Linux 2.6.32.
Ubuntu 8.04.3 LTS also sported the best performance with the C-Ray test profile, which is a ray-tracing benchmark. The difference, however, was quite much smaller.
The Tachyon ray-tracing benchmark performed about the same across the four tested versions of Ubuntu Linux.