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<p class="MsoNormal">Hi Folks,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I wondered if anyone else has managed to run multiple filter-schedulers concurrently under a high load ?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’d thought that the race conditions that we had in the past (where multiple schedulers pick the same host) been eliminated through the reworking of the resource tracker / retry mechanism, but whilst it is much better I still see the odd
case where a request gets rejected multiple times (and eventually fails) because on each successive host it fails to get the resources the scheduler thought were there.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I guess on reflection its implicit in any solution which relies on fail / retry approach to cover the race condition that under a large load the number of retries for any specific request is effectively unlimited, and so no value of max_retries
is ever going to be quite big enough – but before I do some more head scratching about how (if) to try and make this more robust under load I’d see if others have approach this I thought I’d ask if others were also trying to rune more than one active scheduler.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks,<o:p></o:p></p>
<p class="MsoNormal">Phil <o:p></o:p></p>
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