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<br><div><div>On 15 Nov 07, at 1504, Michael Bacon wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div>Interesting thought. We haven't gone to ZFS yet, although I like the idea </div><div>a lot. My hunch is it's an enormous win for the mailbox partitions, but </div><div>perhaps it's not a good thing for the meta partition. I'll have to let </div><div>someone else who knows more about ZFS and write speeds vs. read speeds </div><div>chime in here.</div></blockquote><br></div><div><font class="Apple-style-span" face="Calibri">We're finding it a real win for the meta-partition. We're handing ~1000 users on a 2-way stripe by two-way mirror on the internal disks in a T2000 for the meta-data, with the message data coming in over NFS. We do see a few spikes of write operations (this is one instance from zpool isotat -v 1):</font></div><div><br class="webkit-block-placeholder"></div><div><div><font class="Apple-style-span" color="#000000"><font class="Apple-style-span" face="Courier" size="3"><span class="Apple-style-span" style="font-size: 12px;"> capacity operations bandwidth</span></font></font></div><div><font class="Apple-style-span" color="#000000"><font class="Apple-style-span" face="Courier" size="3"><span class="Apple-style-span" style="font-size: 12px;">pool used avail read write read write</span></font></font></div><div><font class="Apple-style-span" color="#000000"><font class="Apple-style-span" face="Courier" size="3"><span class="Apple-style-span" style="font-size: 12px;">------------ ----- ----- ----- ----- ----- -----</span></font></font></div><div><font class="Apple-style-span" color="#000000"><font class="Apple-style-span" face="Courier" size="3"><span class="Apple-style-span" style="font-size: 12px;">pool1 52.1G 25.9G 4 657 3.96K 3.71M</span></font></font></div><div><font class="Apple-style-span" color="#000000"><font class="Apple-style-span" face="Courier" size="3"><span class="Apple-style-span" style="font-size: 12px;"> mirror 26.0G 13.0G 4 354 3.96K 1.42M</span></font></font></div><div><font class="Apple-style-span" color="#000000"><font class="Apple-style-span" face="Courier" size="3"><span class="Apple-style-span" style="font-size: 12px;"> c0t0d0s4 - - 0 135 0 1.42M</span></font></font></div><div><font class="Apple-style-span" color="#000000"><font class="Apple-style-span" face="Courier" size="3"><span class="Apple-style-span" style="font-size: 12px;"> c0t1d0s4 - - 0 126 63.4K 1.42M</span></font></font></div><div><font class="Apple-style-span" color="#000000"><font class="Apple-style-span" face="Courier" size="3"><span class="Apple-style-span" style="font-size: 12px;"> mirror 26.0G 13.0G 0 302 0 2.29M</span></font></font></div><div><font class="Apple-style-span" color="#000000"><font class="Apple-style-span" face="Courier" size="3"><span class="Apple-style-span" style="font-size: 12px;"> c0t2d0s4 - - 0 112 0 2.29M</span></font></font></div><div><font class="Apple-style-span" color="#000000"><font class="Apple-style-span" face="Courier" size="3"><span class="Apple-style-span" style="font-size: 12px;"> c0t3d0s4 - - 0 109 0 2.29M</span></font></font></div><div><font class="Apple-style-span" color="#000000"><font class="Apple-style-span" face="Courier" size="3"><span class="Apple-style-span" style="font-size: 12px;">------------ ----- ----- ----- ----- ----- -----</span></font></font></div><div><br class="webkit-block-placeholder"></div><div><br class="webkit-block-placeholder"></div><div><font class="Apple-style-span" color="#000000"><font class="Apple-style-span" face="Calibri">but it's showing no signs at all of being IO bound on the metadata. The spikes are really just spikes for a second: the typical level is about 10 ops / disk / sec. </font></font></div><div><font class="Apple-style-span" face="Calibri"><br class="webkit-block-placeholder"></font></div><div><font class="Apple-style-span" face="Calibri">ian</font></div><div><font class="Apple-style-span" face="Calibri"><br class="webkit-block-placeholder"></font></div></div></body></html>