SSD vs Flash based SANs – Oracle DB I/O comparison

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SSD vs Flash based SANs – I/O comparison
During a storage migration project from SSD based SAN  and Flash based SAN,  we have performed following tests to compare the I/O performance. On each of the tests it was observed flash was outperforming the SSD SAN on various magnitudes.
This is not a comprehensive load test, but this acted more as a POC to go ahead with the flash implementation.

1.      File Creation using “dd” command

10 G File Creation
root@prt51fin2 # date;time dd if=/dev/zero of=/xiv-test1/xivtest count=10240        bs=1048576;date
Wed Jan 24 17:20:32 IST 2018
10240+0 records in
10240+0 records out

real    1m16.735s
user    0m0.043s
sys     0m8.783s
Wed Jan 24 17:21:49 IST 2018
root@prt51fin2 #



----------------------------------------------------------------------------------



root@prt51fin2 # date;time dd if=/dev/zero of=/flash-test/flashtest count=10240 bs=1048576;date
Wed Jan 24 17:23:35 IST 2018
10240+0 records in
10240+0 records out

real    0m20.672s
user    0m0.037s
sys     0m7.034s
Wed Jan 24 17:23:56 IST 2018
root@prt51fin2 #





20 G File Creation


root@prt51fin2 # date;time dd if=/dev/zero of=/xiv-test1/xivtest count=20480 bs=1048576;date
Wed Jan 24 17:27:00 IST 2018
20480+0 records in
20480+0 records out

real    2m24.082s
user    0m0.086s
sys     0m16.639s
Wed Jan 24 17:29:24 IST 2018
root@prt51fin2 #

----------------------------------------------------------------------------------

root@prt51fin2 # date;time dd if=/dev/zero of=/flash-test/flashtest count=20480 bs=1048576;date
Wed Jan 24 17:30:09 IST 2018
20480+0 records in
20480+0 records out

real    0m43.506s
user    0m0.072s
sys     0m14.124s
Wed Jan 24 17:30:52 IST 2018






2.      asm io commands




ASM IO operations were performed
via data file creations and the times were compared. During the ASM data file
creation disk service times were also monitored where the flash had ~5X less
service times again.








SSD










Flash









3.     
Orion test 



Finally, Orion test was performed
on SSD and Flash disks. With small I/O operations flash was outperforming SSD by significant margin. Orion results are attached here with.



SSD_Flash Orion test results









































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