On my test system, with the two new disks and with the three domU guest systems set up and running (but not connected to the outside world, so the load is obviously lower), I run tiobench in the dom0. Executive summary:
read/write rates around 5 times faster, and no awful latency. The worse latency on the Caviar disks was 121588.99 ms, and on these disks it’s 6077.56 ms.
I can’t wait to get these disks over to the colo. If all goes well, it will just be a simple matter of shutting down the domUs, making a final copy from the old disks to the new disks, and then swapping the disks.
Full details below the cut.
No size specified, using 2000 MB
Unit information
================
File size = megabytes
Blk Size = bytes
Rate = megabytes per second
CPU% = percentage of CPU used during the test
Latency = milliseconds
Lat% = percent of requests that took longer than X seconds
CPU Eff = Rate divided by CPU% - throughput per cpu load
Sequential Reads
File Blk Num Avg Maximum Lat% Lat% CPU
Identifier Size Size Thr Rate (CPU%) Latency Latency >2s >10s Eff
---------------------------- ------ ----- --- ------ ------ --------- ----------- -------- -------- -----
2.6.32-5-xen-amd64 2000 4096 1 104.39 38.18% 0.036 71.20 0.00000 0.00000 273
2.6.32-5-xen-amd64 2000 4096 2 168.03 145.4% 0.044 110.11 0.00000 0.00000 116
2.6.32-5-xen-amd64 2000 4096 4 171.72 272.9% 0.080 258.17 0.00000 0.00000 63
2.6.32-5-xen-amd64 2000 4096 8 159.19 490.6% 0.177 464.87 0.00000 0.00000 32
Random Reads
File Blk Num Avg Maximum Lat% Lat% CPU
Identifier Size Size Thr Rate (CPU%) Latency Latency >2s >10s Eff
---------------------------- ------ ----- --- ------ ------ --------- ----------- -------- -------- -----
2.6.32-5-xen-amd64 2000 4096 1 0.55 1.150% 7.122 63.11 0.00000 0.00000 48
2.6.32-5-xen-amd64 2000 4096 2 1.07 3.731% 7.264 62.82 0.00000 0.00000 29
2.6.32-5-xen-amd64 2000 4096 4 1.17 4.832% 13.079 88.93 0.00000 0.00000 24
2.6.32-5-xen-amd64 2000 4096 8 1.35 12.47% 22.671 153.44 0.00000 0.00000 11
Sequential Writes
File Blk Num Avg Maximum Lat% Lat% CPU
Identifier Size Size Thr Rate (CPU%) Latency Latency >2s >10s Eff
---------------------------- ------ ----- --- ------ ------ --------- ----------- -------- -------- -----
2.6.32-5-xen-amd64 2000 4096 1 70.68 61.47% 0.053 322.24 0.00000 0.00000 115
2.6.32-5-xen-amd64 2000 4096 2 67.38 145.6% 0.110 524.87 0.00000 0.00000 46
2.6.32-5-xen-amd64 2000 4096 4 64.97 342.9% 0.228 1004.67 0.00000 0.00000 19
2.6.32-5-xen-amd64 2000 4096 8 61.39 803.3% 0.471 1328.05 0.00000 0.00000 8
Random Writes
File Blk Num Avg Maximum Lat% Lat% CPU
Identifier Size Size Thr Rate (CPU%) Latency Latency >2s >10s Eff
---------------------------- ------ ----- --- ------ ------ --------- ----------- -------- -------- -----
2.6.32-5-xen-amd64 2000 4096 1 1.36 0.940% 0.535 1522.11 0.00000 0.00000 145
2.6.32-5-xen-amd64 2000 4096 2 1.55 3.210% 0.380 1022.24 0.00000 0.00000 48
2.6.32-5-xen-amd64 2000 4096 4 1.59 12.08% 0.140 53.50 0.00000 0.00000 13
2.6.32-5-xen-amd64 2000 4096 8 1.50 16.98% 5.722 6077.56 0.12500 0.00000 9