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</o:shapelayout></xml><![endif]--></head><body lang=DE link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal>Hi,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span lang=EN-US>I have about 600GB in my sheepdog cluster. A recovery of one node has started today morning and it is at 20% after 2h, so it will still take another 8h. I would like to put more vm’s in the cluster, but then recovery would take even longer…<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>During recovery there is a lot of disk read activity on the recovery node and on other nodes, because (as far as I understand) hashes for the data blocks are computed and compared. This disk activity is so heavy, that other vm’s that are still running out of qcow2 files, have a notable performance impact. <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>If I imagine I have more data in the sheepdog cluster and recovery might take 2 days, all my vm’s running slow for two days, this will not be accepted by my users, but sometime a recovery might be necessary (e.g. server reboot or sheep crash like today morning).<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>So the question is how can this recovery process speed up? <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>From my current knowledge (which is not too deep), the only idea would be to calculate the data block hashes during storing of the data block and compare only stored hashes. Would this be possible/make sense or is there a better solution?<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>I really find sheepdog a great solution and I appreciate all your work you put into sheepdog and I really like to use it in production, but recovery performance really is an issue for me.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Thanks & Regards<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Gerald<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US> <o:p></o:p></span></p></div></body></html>