On Apr 19, 2011, at 8:49 AM, Laurent Laborde wrote:
Write Mode: 10% Stallcheck at 1.000000 Verbose Unknown units of blocks Arg: 1 Read 1000000 blocks Added /home/ssd/big1 2.01%, 20122 read, 1978 written, 16097.57kB/sec 2012.20 iops 2.01%, 3 read, 0 written, 2.40kB/sec 0.30 iops 2.01%, 3 read, 0 written, 2.40kB/sec 0.30 iops 2.01%, 3 read, 0 written, 2.40kB/sec 0.30 iops 3.82%, 18036 read, 1779 written, 14428.73kB/sec 1803.59 iops 4.03%, 2175 read, 209 written, 1739.98kB/sec 217.50 iops 4.03%, 3 read, 0 written, 2.40kB/sec 0.30 iops 4.03%, 2 read, 0 written, 1.60kB/sec 0.20 iops 4.04%, 4 read, 0 written, 3.20kB/sec 0.40 iops 4.04%, 4 read, 0 written, 3.20kB/sec 0.40 iops
The performance here looks like the old jmicron based ssds that had absolutely abysmal performance - the intel x25s do not suffer like this. The x25's however suffer from the power durability Greg has mentioned. (And they will eventually need to be security erase'd to restore performance - you'll start getting major write stalls). Looks like you were on the cusp of stalling here.
btw, yay pgiosim! :) -- Jeff Trout <jeff@xxxxxxxxxxxxx> http://www.stuarthamm.net/ http://www.dellsmartexitin.com/ -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
