Hi, I've noticed a noticeable disk IO performance decrease in 9.3 vs. 9.1. To test I've been running the following command: time dd if=/dev/zero of=bigfile bs=8k count=500000 Here are some representative numbers for three fairly comparable machines: 9.1 machine: 2*Opteron 242, 2 GB RAM 2 IDE drives (hda,hdc) ST312022A in SW RAID 1 kernel: 2.6.5-7.145-smp dd time: 103seconds ~ 39.8MB/Sec 9.3 machine: 2*Opteron 242, 1 GB RAM 2 IDE drives (hda,hdc) ST3120026A in SW RAID 1 kernel: 2.6.11.4-20a-smp dd time: 608seconds ~ 6.7MB/Sec 9.3 machine 2*Opteron 246, 1 GB RAM 2 IDE drives (hda,hdc) ST3120026A in SW RAID 1 kernel: 2.6.11.4-20a-smp dd time: 228seconds ~ 17.9MB/Sec All machines were idle while running the test. All filesystems are Reiser 3.6. - Has anyone noticed a disk performance degradation moving from 9.1 to 9.3? - What can I do to track down the cause of the difference between the 9.1 machine and the two 9.3 machines as well as the fast vs. slow 9.3 machine? -K