On Fri, 2 Nov 2012, Peter Ross wrote: > Just for ZFS (under FreeBSD): I have throttle inbetween (15 Megabit/second) > because it was "hammering" the disks to a stand still for the rest of the > system. > > Yep, this, the 20% free space and the generous use of RAM are my main issues > with ZFS but they are not big enough to outweight the advantages I see in > everyday administration.
"Generous memory usage" indeed. My zfs server with 4GB of ram crashes once a week on average with zfs arc backtraces or just livelocks with txg_sync taking 100% CPU usage (with no zfs access, which is bad for a machine with zfs mounted /var by necessity of /boot being a 128MB flash IDE card and / being a 8GB USB nanostick). Each -rc release says "we finally fixed that txg_sync and arc_reclaim issue", but alas it never comes good. My favourite is where sometimes mysteriously arc usage increases tens of times beyond arc_max before the machine grinds to a halt. Someone ballsed up the memory accounting! (Just saying this just in case anyone thought zfs was preduction ready yet. Apparently the same issues sometimes affects bsd and indiana). > The snapshots (and zfs send/receive - I mirror every mission-critical > filesystem to a "partner" machine) are part of the advantages, it is all very > easy. I am surprised people find zfs send so useful though. My only use for it would be if I could get data of it onto another filesystem at close to wire speed :) I mean, I thought it was pretty routine back in days of yore to do an: lvm snapshot dd if=/dev/base/home-snap | ssh blah dd of=/dev/base/home Ok, a couple more commands, but infinitely flexible. -- Tim Connors _______________________________________________ luv-main mailing list [email protected] http://lists.luv.asn.au/listinfo/luv-main
