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<p class="MsoNormal">I have 2 openstack clusters running the Folsom release with multiple Swift nodes. I also have a small setup that is running only Swift with a single node. I’m noticing very large Swift I/O latencies (seconds long) on the openstack clusters
– ssbench output snippet is below. Performance is approximately identical on the openstack clusters. The Swift only cluster performs much better.
<o:p></o:p></p>
<p class="MsoNormal">Setup differences:<o:p></o:p></p>
<p class="MsoNormal" style="text-indent:.5in">Openstack clusters are using Keystone authentication – Swift only setup uses temp auth.<o:p></o:p></p>
<p class="MsoNormal" style="text-indent:.5in">Multiple Swift nodes on openstack clusters – Swift only has single node.<o:p></o:p></p>
<p class="MsoNormal" style="text-indent:.5in"><o:p> </o:p></p>
<p class="MsoNormal">I also see that all object I/Os are being sent to the 2<sup>nd</sup> Swift node, there are no objects on the 1<sup>st</sup> swift node. Both nodes are running swift-proxy services.<o:p></o:p></p>
<p class="MsoNormal">I have LOG_LOCAL0 set in the environment and also logging enabled in /etc/swift/swift.conf, but haven’t seen any log entries made.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">What can I look at to debug the cause of the excessive latencies on both of these stacks?<o:p></o:p></p>
<p class="MsoNormal">I’d also like to determine why all objects are on the 2<sup>nd</sup> swift node and none on the 1<sup>st</sup> node.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’m supposed to do performance evaluations but need to fix the latency problem first.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Ssbench output snippet:<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in">TOTAL<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> Count: 50 Average requests per second: 9.2<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> min max avg std_dev 95%-ile Worst latency TX ID<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> First-byte latency: 0.067 - 2.513 0.390 ( 0.604) 1.948 (all obj sizes) txae75691d37d544b4ac0cfe3b8cba7f38<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> Last-byte latency: 0.067 - 3.337 0.430 ( 0.695) 1.997 (all obj sizes) txdcedb82227654b338daa85751f6d1232<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> First-byte latency: 0.070 - 2.513 0.542 ( 0.749) 2.255 ( tiny objs) txae75691d37d544b4ac0cfe3b8cba7f38<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> Last-byte latency: 0.070 - 2.514 0.468 ( 0.659) 1.997 ( tiny objs) txae75691d37d544b4ac0cfe3b8cba7f38<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> First-byte latency: 0.067 - 1.884 0.251 ( 0.382) 0.695 ( small objs) tx2ceec827f3304530b01a0d5993eea2e8<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> Last-byte latency: 0.067 - 3.337 0.385 ( 0.732) 1.884 ( small objs) txdcedb82227654b338daa85751f6d1232<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif"">Thanks,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif"">Tim<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Arial","sans-serif"">Timothy Snider</span></b><span style="font-size:10.0pt;font-family:"Arial","sans-serif""><br>
Strategic Planning & Architecture - Advanced Development</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><b><span style="font-size:10.0pt;font-family:"Arial","sans-serif"">NetApp</span></b><span style="font-size:10.0pt;font-family:"Arial","sans-serif""><br>
316-636-8736 Direct Phone<br>
316-213-0223 Mobile Phone<br>
tim.snider@netapp.com</span><span style="font-size:12.0pt;font-family:"Times New Roman","serif""><br>
<a href="http://www.netapp.com/?ref_source=eSig"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:blue">netapp.com</span></a><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:10.0pt;font-family:"Arial","sans-serif""> </span><span style="font-size:12.0pt;font-family:"Times New Roman","serif""><img border="0" width="124" height="35" id="Picture_x0020_1" src="cid:image001.gif@01CE7C76.E2F2C830" alt="Description: http://media.netapp.com/images/netapp-logo-sig-5.gif"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif""><o:p> </o:p></span></p>
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