On Mar 14, 2012, at 5:05 PM, madhusudhana wrote: >> I am yet to fully understand Ceph's behavior, thus you should not take my word on it, but I believe Ceph will >> automatically take snapshots as a checkpointing mechanism. So, until someone (*looks at Sage*) >> declares I am completely and utterly wrong, I'm going with that assumption. >> >> Also, I am not sure if the slowdown you're suffering is Btrfs-related, but just in case... >> >>> >>> One more concern is 'rm' command is also TOO slow. I am a newbie here and >>> i don't know to much about ceph working. I configured it in a simple way. >>> Install ceph and run mkcephfs and start ceph in all the servers in the >>> cluster. >>> >>> I want to understand why basic operations like 'cp' and 'rm' are slow bcz >>> my actual workload does a lot of copy and delete operation. If I find the >>> reason for the slowness and get a fix, then I think i can better compare and >>> complete my ceph evaluation. >> >> My follow up questions: >> >> - Are you copying into Ceph? From within Ceph, into Ceph? Or are you simply copying from Ceph to somewhere else? > Am copying data from a linux machine to ceph. Bot cp and rsync are really really slow Although this could trigger a Btrfs-specific behavior we've noticed a while ago... >> >> - Under which conditions do these slowdowns happen? Are you performing *a lot* of cp's / rm's in a short >> amount of time? > Its doesn't matter whether i am doing cp/rm in a short. Whenever i run those > commands they run really slow. ... I don't think this applies. If it happens every time you perform a cp/rm, regardless what's happening on the file system, and specially if it happens even if it's just the occasional cp/rm, well... then I think this does not fulfill the requirements for my initial suspicion. This may be Ceph-related, so I'll leave it to someone else who might be able to help you better than I am. :-) Good luck. Cheers, Joao --- João Eduardo Luís gpg key: 477C26E5 from pool.keyserver.eu
Attachment:
PGP.sig
Description: This is a digitally signed message part
