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Hi everyone,<br>
<br>
Here are some current ZFS/DMU benchmark results that might be of
interest to you.<br>
These results were obtained on a Sunfire x4500 with these
specifications:<br>
<br>
- 2 dual-core AMD Opteron processors<br>
- 16 GB main memory<br>
- 48 SATA II HDD (7200 RPM, 500 GB each)<br>
- Solaris 10 update 3<br>
- Userspace DMU from OpenSolaris build 74<br>
<br>
The tool used in this particular benchmark was PIOS, which simulates a
parallel I/O load typically experienced by an OSS. Since PIOS links
directly with the DMU, it should give a good estimation of the
maximum throughput of the userspace DMU-OSS. For comparison, you can
also see the results of running the same PIOS benchmark with normal
POSIX I/O on the Solaris 10u3 ZFS implementation.<br>
<br>
See the attached PDF for the results.<br>
<br>
First page provides PIOS throughput information on striped pools with
10, 24 and 46 disks. uDMU outperforms kernel ZFS with 10 disks,
however, the kernel ZFS implementation scales
better to 24 and 46 disks. Surprisingly enough, disabling checksums has
a negative impact on the throughput
with a 10-disk striped pool. This impact can be attributed to the
differences in the uDMU IO pipeline which are probably causing the IOs
to not being parallelized when checksumming is disabled. This issue,
however, should not be hard to fix.<br>
<br>
Second page shows the results of running PIOS on RAID-Z,
RAID-Z2 and mirrored pools. In these configurations, the kernel ZFS
currently has a better throughput than the userspace DMU.<br>
<br>
These results were obtained with only minimal tuning of the
DMU (setting a maximum cache size and increasing the number of I/O
threads). Work is already underway to improve the performance of the
DMU and we expect to see better throughput in the coming months.<br>
<br>
Best regards,<br>
Ricardo<br>
<br>
<div class="moz-signature">-- <br>
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<td height="121" width="121"><a href="http://www.sun.com"><img
moz-do-not-send="true" src="http://www.sun.com/emrkt/sigs/6g_top.gif"
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<td style="font-family: Arial; font-size: 10px;" height="121"
width="329"><b> Ricardo Manuel Correia </b><br>
<br>
Lustre Engineering Group<br>
<b>Sun Microsystems, Inc.</b><br>
Portugal<br>
<br>
<a class="moz-txt-link-abbreviated"
href="mailto:Ricardo.M.Correia@Sun.COM">Ricardo.M.Correia@Sun.COM</a><br>
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