3 ms·
It's worth noting that you can speed up write operations on EBS volumes by first initializing them by writing data to every block on the volume. Subsequent writ
by spudlyo 17y ago
It's worth noting that you can speed up write operations on EBS volumes by first initializing them by writing data to every block on the volume. Subsequent writes will be faster due to the way Amazon virtualizes disks.
http://docs.amazonwebservices.com/AWSEC2/2007-08-29/DeveloperGuide/instance-storage.html http://docs.amazonwebservices.com/AWSEC2/2007-08-29/Develope...
- aolnerd 17y agoThose docs refer to ephemeral storage. I haven't seen any claims by Amazon or test results that indicate it is also true for EBS volumes. I have been meaning to test this myself.
- spudlyo 17y agogracie:~# time dd if=/dev/zero of=/dev/sdl bs=1024k count=10240 10240+0 records in 10240+0 records out 10737418240 bytes (11 GB) copied, 344.745 seconds, 31.1 MB/s real 5m44.748s user 0m0.025s sys 0m10.152s gracie:~# time dd if=/dev/zero of=/dev/sdl bs=1024k count=10240 10240+0 records in 10240+0 records out 10737418240 bytes (11 GB) copied, 217.106 seconds, 49.5 MB/s real 3m37.125s user 0m0.023s sys 0m10.268s gracie:~# time dd if=/dev/zero of=/dev/sdl bs=1024k count=10240 10240+0 records in 10240+0 records out 10737418240 bytes (11 GB) copied, 247.319 seconds, 43.4 MB/s real 4m7.323s user 0m0.036s sys 0m9.794s EDIT: I ran it a third time just to make sure the results held. I'd still take this with a grain of salt, in my experience EBS i/o results are pretty inconsistent.
- 3ijsflksflk 17y agodata rules