Hello Mark, Monday, September 11, 2006, 4:25:40 PM, you wrote:
MM> Jeremy Teo wrote: >> Hello, >> >> how are writes distributed as the free space within a pool reaches a >> very small percentage? >> >> I understand that when free space is available, ZFS will batch writes >> and then issue them in sequential order, maximising write bandwidth. >> When free space reaches a minimum, what happens? >> >> Thanks! :) >> MM> Just what you would expect to happen: MM> As contiguous write space becomes unavailable, writes will be come MM> scattered and performance will degrade. More importantly: at this MM> point ZFS will begin to heavily write-throttle applications in order MM> to ensure that there is sufficient space on disk for the writes to MM> complete. This means that there will be less writes to batch up MM> in each transaction group for contiguous IO anyway. MM> As with any file system, performance will tend to degrade at the MM> limits. ZFS keeps a small overhead reserve (much like other file MM> systems) to help mitigate this, but you will definitely see an MM> impact. I hope it won't be a problem if space is getting low i a file system with quota set however in a pool the file system is in there's plenty of space, right? -- Best regards, Robert mailto:[EMAIL PROTECTED] http://milek.blogspot.com _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
