On Fri, Aug 24, 2012 at 12:57 AM, MORITA Kazutaka <morita.kazutaka at lab.ntt.co.jp> wrote: > At Fri, 24 Aug 2012 00:34:24 +0800, > Yunkai Zhang wrote: >> >> On Thu, Aug 23, 2012 at 10:20 PM, MORITA Kazutaka >> <morita.kazutaka at lab.ntt.co.jp> wrote: >> > At Thu, 23 Aug 2012 21:46:55 +0800, >> > Yunkai Zhang wrote: >> >> >> >> When inconsistency happens, in the worst case, we just need to make >> >> replicas with the same value but needn't to care about which replica >> >> is correct. >> >> >> >> But in the best case, only several objects were polluted, then this >> >> patch can give us a chance to verify them, This patch is used to work >> >> with 'collie vdi check' command, that is my original intention when >> >> developed it. >> > >> > Well, replica inconsistency happens only when the VM terminates >> > unexpectedly. If the vm image needs a fix, the guest os filesystem >> > should fix it. What sheepdog should do is only keeping consistency so >> >> Can you explain how the guest os files system fix it? > > I meant fsck. If correct one have been removed, how can fsck fix that? (I'm not familiar with this command, I just have some doubts.) > > I don't fully understand yet what situation you want to avoid. What > kinds of problem happens to you if you fix consistency with wrong > objects? If fsck can help me to fix, I have no question, and this patch isn't very important for me. I just want to try our best to protect sheepdog's data integrity, I haven't encountered any situation in real work, I didn't even encountered VM's unexpected termination. If fix consistency with wrong objects is really not harm, I do not mind to drop this patch. > > Thanks, > > Kazutaka -- Yunkai Zhang Work at Taobao |