Oddly enough, the performance of a 3Ware 9550SX controller seems to have improved when switching from 64-bit to 32-bit CentOS 5. This is a RAID0 device with 8 x 500gig barracudas and the noatime and data=writeback tweaks to that device in /etc/fstab. It's also quite a bit better than results on the same machine using CentOS 4.4 (64-bit). This partition is used to store scratch data consisting of large uncompressed video files so the fast block reads/writes are a real help. Nice job fellas! [localhost data]$ /usr/sbin/bonnie++ -f Writing intelligently...done Rewriting...done Reading intelligently...done start 'em...done...done...done... Create files in sequential order...done. Stat files in sequential order...done. Delete files in sequential order...done. Create files in random order...done. Stat files in random order...done. Delete files in random order...done. Version 1.03 ------Sequential Output------ --Sequential Input- --Random- -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks-- Machine Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP /sec %CP localhost.locald 4G 269292 97 182099 64 474707 72 676.3 1 ------Sequential Create------ --------Random Create-------- -Create-- --Read--- -Delete-- -Create-- --Read--- -Delete-- files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP 16 +++++ +++ +++++ +++ +++++ +++ +++++ +++ +++++ +++ +++++ +++ localhost.localdomain,4G,,,269292,97,182099,64,,,474707,72,676.3,1,16,+++++,+++,+++++,+++,+++++,+++,+++++,+++,+++++,+++,+++++,+++