[Gluster-users] Gluster v 3.3 with KVM and High Availability

[Mark Nipper]

On 12 Jul 2012, Brian Candler wrote:
> I don't believe he is getting that speed with cache=writethrough.  I think
> he means cache=writeback.

	No, I meant writethrough.  Initially I had just done dd
using something like:
---
$ dd if=/dev/zero of=/home/user/testing bs=1024k count=1000
1000+0 records in
1000+0 records out
1048576000 bytes (1.0 GB) copied, 20.1434 s, 52.1 MB/s

This is on a guest with 512MB of RAM.

	But then I added sync and made the file bigger for a
little bit more accuracy:
---
$ dd if=/dev/zero of=/home/user/testing bs=1024k count=2000 conv=sync
2000+0 records in
2000+0 records out
2097152000 bytes (2.1 GB) copied, 53.372 s, 39.3 MB/s

	And finally I just tried fio using:
---
[global]
ioengine=sync
direct=1
rw=write
bs=128k
size=512m
directory=/home/user/data1

[file1]
iodepth=4

[file2]
iodepth=32

[file3]
iodepth=8

[file4]
iodepth=16
---

which gave:
---
  WRITE: io=2048.0MB, aggrb=32217KB/s, minb=8054KB/s, maxb=8212KB/s, mint=63842msec, maxt=65093msec

	That's probably a lot closer to accurate, 32MB/s give or
take.  Sorry for the less than scientific approach initially.  :)

-- 
Mark Nipper
nipsy at bitgnome.net (XMPP)
+1 979 575 3193
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