Re: Slow queries / commits, mis-configuration or hardware issues?

Dne 14.11.2011 22:58, Cody Caughlan napsal(a):
> I ran bonnie++ on a slave node, doing active streaming replication but
> otherwise idle:
> http://batch-files-test.s3.amazonaws.com/sql03.prod.html
>
> bonnie++ on the master node:
> http://batch-files-test.s3.amazonaws.com/sql01.prod.html
>
> If I am reading this right, this is my first time using it, the
> numbers dont look too good.

I've done some benchmarks on my own (m1.xlarge instance), and the
results are these (http://pastebin.com/T1LXHru0):

single drive
------------
dd writes: 62 MB/s
dd reads: 110 MB/s
bonnie seq. writes: 55 MB/s
bonnie seq. rewrite: 33 MB/s
bonnie seq. reads: 91 MB/s
bonnie seeks: 370/s

raid 0 (4 devices)
-----------------------------
dd writes: 220 MB/s
dd reads: 380 MB/s
bonnie seq. writes: 130 MB/s
bonnie seq. rewrite: 114 MB/s
bonnie seq. reads: 280 MB/s
bonnie seeks: 570/s

raid 10 (4 devices)
-----------------------------
dd writes: 90 MB/s
dd reads: 200 MB/s
bonnie seq. writes: 49 MB/s
bonnie seq. rewrite: 56 MB/s
bonnie seq. reads: 160 MB/s
bonnie seeks: 590/s

So the results are rather different from your results (both master and
slave).

What surprises me a bit is the decrease of write performance between
sigle drive and RAID 10. I've used bonnie++ 1.03e, so I'm wondering if
the 1.96 would give different results ...

All those benchmarks were performed with ext3.

Tomas