The majority of the rest of the machines iowait hover around the 1% mark.. CPU time tends to be about the same, just the iowait is much much higher..
Very interesting. data=ordered makes fsync more expensive, since it ends up syncing more then just the buffers for that one file. Could you please try removing data=ordered from machine1?
Ok.. after leaving it for a few minutes..
machine 1: (mounted: noatime,nodiratime,alloc=skip_busy:dirid_groups,packing_groups)
21:48:08 up 12:49, 1 user, load average: 0.57, 0.74, 0.92
338 processes: 337 sleeping, 1 running, 0 zombie, 0 stopped
CPU states: cpu user nice system irq softirq iowait idle
total 9.6% 0.0% 39.2% 0.0% 1.2% 6.8% 342.0%
cpu00 2.2% 0.0% 12.4% 0.1% 0.7% 1.3% 82.9%
cpu01 2.6% 0.0% 9.1% 0.0% 0.1% 1.9% 86.0%
cpu02 2.4% 0.0% 9.0% 0.0% 0.0% 0.9% 87.5%
cpu03 2.6% 0.0% 8.9% 0.0% 0.0% 2.6% 85.6%
At first i thought that it *might* be just this machine itself, so i rebooted machine2 with the same kernel patches..
machine 2: (mounted: noatime,nodiratime,alloc=skip_busy:dirid_groups,packing_groups)
21:46:24 up 7 min, 1 user, load average: 0.85, 0.64, 0.27
315 processes: 314 sleeping, 1 running, 0 zombie, 0 stopped
CPU states: cpu user nice system irq softirq iowait idle
total 9.6% 0.0% 34.8% 0.0% 1.2% 7.2% 346.4%
cpu00 2.5% 0.0% 7.1% 0.1% 1.1% 2.1% 86.8%
cpu01 2.6% 0.0% 8.0% 0.0% 0.1% 1.1% 87.8%
cpu02 2.4% 0.0% 10.9% 0.0% 0.1% 1.7% 84.6%
cpu03 2.1% 0.0% 8.6% 0.0% 0.0% 2.3% 86.8%
machine 3->8: (mounted: noatime,nodiratime)
21:46:21 up 1 day, 9:12, 1 user, load average: 1.07, 2.24, 1.88
295 processes: 294 sleeping, 1 running, 0 zombie, 0 stopped
CPU states: cpu user nice system irq softirq iowait idle
total 11.2% 0.0% 40.8% 0.0% 2.0% 1.6% 343.2%
cpu00 2.7% 0.0% 10.4% 0.1% 1.5% 0.3% 84.7%
cpu01 3.0% 0.0% 10.1% 0.0% 0.1% 0.5% 85.9%
cpu02 2.6% 0.0% 11.1% 0.0% 0.1% 0.5% 85.3%
cpu03 2.8% 0.0% 9.2% 0.0% 0.1% 0.3% 87.2%What i then tried on machine1 was remounting it noatime,nodiratime and what was wierd was that the iowait stayed exactly the same, no indication of dropping at all.. Does the kernel patches change any of the default mount options at all? If i put the stock 2.6.5 kernel back on without the patch applied and mount it back as noatime,nodiratime, the iowait drops back to its normal 1%..
Cami
