Yeb Havinga wrote:
Yeb Havinga wrote:
diskchecker: running 37 sec, 4.47% coverage of 500 MB (1468 writes;
39/s)
Total errors: 0
:-)
OTOH, I now notice the 39 write /s .. If that means ~ 39 tps... bummer.
When playing with it a bit more, I couldn't get the test_file to be
created in the right place on the test system. It turns out I had the
diskchecker config switched and 39 write/s was the speed of the
not-rebooted system, sorry.
I did several diskchecker.pl tests this time with the testfile on the
SSD, none of the tests have returned an error :-)
Writes/s start low but quickly converge to a number in the range of 1200
to 1800. The writes diskchecker does are 16kB writes. Making this 4kB
writes does not increase writes/s. 32kB seems a little less, 64kB is
about two third of initial writes/s and 128kB is half.
So no BBU speeds here for writes, but still ~ factor 10 improvement of
iops for a rotating SATA disk.
regards,
Yeb Havinga
PS: hdparm showed write cache was on. I did tests with both ext2 and
xfs, where xfs tests I did with both barrier and nobarrier.
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