My results using Bonnie: Computer tested on is a home brew: GIGABYTE K8NPRO-SLI Motherboard - nForce4 SLI Socket 939 PCI-E AMD Athlon 64 X2 Dual-core 4400 (2.2Ghz) Memory 2ea. DDR400 1024MB EL TITANIUM OCZ (2Gbytes total) eVGA GeForce 6200 TC PCI-E 64MB 2N22 USB keyboard and mouse Disks - All internal and connected directly to motherboard: Primary - MAXTOR 300GB 7200RPM Hard Drive - 16MB IDE (ATA 133) 4 Disks SATA - WESTERN DIGITAL 250GB 7200RPM Hard Drive - 16MB SATA2 - OEM (WD2500KS) Note: SATA disks running in SATA II RAID5 (zfsr5) consists of zfs software created RAID5 using the 4 SATA disks. NON-RAID (zfsstd) consists of zfs created file sytem on the Primary disk. Bonnie was built using Sun Studio11 with the -xarch=amd64 switch. RESULTS: RAID5 Tests: UNLOADED: -------Sequential Output-------- ---Sequential Input-- --Random-- -Per Char- --Block--- -Rewrite-- -Per Char- --Block--- --Seeks--- Machine MB K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU /sec %CPU zfsr5 16384 70912 94.3 87655 23.4 39933 11.3 61753 81.2 62313 7.4 190.2 2.1 LOADED: -------Sequential Output-------- ---Sequential Input-- --Random-- -Per Char- --Block--- -Rewrite-- -Per Char- --Block--- --Seeks--- Machine MB K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU /sec %CPU zfsr5 16384 49566 65.0 87636 22.1 39620 14.1 62101 83.0 62585 10.3 179.5 2.9 STANDARD ATA 133 Tests: UNLOADED: -------Sequential Output-------- ---Sequential Input-- --Random-- -Per Char- --Block--- -Rewrite-- -Per Char- --Block--- --Seeks--- Machine MB K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU /sec %CPU zfsstd 16384 27808 36.8 34478 10.7 19854 5.5 47180 64.3 48150 9.8 122.8 1.4 LOADED: -------Sequential Output-------- ---Sequential Input-- --Random-- -Per Char- --Block--- -Rewrite-- -Per Char- --Block--- --Seeks--- Machine MB K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU /sec %CPU zfsstd 16384 27463 36.4 37334 10.0 20565 12.8 47381 65.6 47414 21.3 119.6 2.4 OBSERVATIONS: The only noteworthy delta is the RAID5 Loaded Sequential Per Char is 30% less than the Unloaded condition. The variations in the balance are neglible. This message posted from opensolaris.org