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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">Would an OpenStack cinder volume meet your needs ?<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">Tim<o:p></o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif"> David Arroyo [mailto:droyo@aqwari.net]
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<b>Sent:</b> 29 August 2015 17:17<br>
<b>To:</b> openstack-operators@lists.openstack.org<br>
<b>Subject:</b> [Openstack-operators] Passing entire disks to instances<o:p></o:p></span></p>
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<p class="MsoNormal">Hello,<o:p></o:p></p>
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<p class="MsoNormal">I would like to pass entire disks to my openstack instances. I have some IO-bound workloads and would like to avoid any overhead or contention by giving an instance access to N additional disks, such that they do not share that disk with
other guests on the same compute node.<o:p></o:p></p>
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<p class="MsoNormal">These additional disks do not need to last longer than the instances themselves; they are "ephemeral" in that regard. There is no need for backup, no need for instance or data migration, and no need for running the instance on a separate
compute node from the extra disks. Effectively I want to have an "extra disks" property, as part of a flavor or image, that is handled like vcpus without overcommit.<o:p></o:p></p>
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<p class="MsoNormal">I have been doing some research but have not yet found an obvious way to do this in openstack. Does anyone else have a similar use case, and how have you handled it? To be more specific, we run some very large Cassandra clusters on physical
hardware, with excellent performance. Cassandra is largely IO-bound, and we want to virtualize it without introducing unnecessary IO latency.<o:p></o:p></p>
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<p class="MsoNormal">Cheers,<o:p></o:p></p>
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<p class="MsoNormal">David<o:p></o:p></p>
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