Re: fsck of big disk
Valerio Daelli wrote: Hi list we have a freshly installed FreeBSD 6.2 machine with a gstriped external disk, of 5.3Tb. The disk is composed of two slices of 2.6 Tb. We are trying to have a (background) fsck of it but few hours later since the start of the check the host get unresponsive: it responds to ping but it doesn't let login anyone, nor by ssh nor by console. What do you get if you press Control-T on the console when it is unresponsive? When you do a background fsck there is a point at which a snapshot of the filesystem is taken, although I'd say that happens at the beginning of the check. The problem is that with 5.3 Tb, it may take quite a while to take the snapshot, and during that time the system blocks any process that tries to write to the filesystem. Maybe that's what you are experiencing. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: fsck of big disk
Hi, thanks a lot for your answer. we have a freshly installed FreeBSD 6.2 machine with a gstriped external disk, of 5.3Tb. The disk is composed of two slices of 2.6 Tb. We are trying to have a (background) fsck of it but few hours later since the start of the check the host get unresponsive: it responds to ping but it doesn't let login anyone, nor by ssh nor by console. What do you get if you press Control-T on the console when it is unresponsive? We are not able to login via console nor via ssh. Pheraps you suggest me to press Control-T on the console even if I am not logged on. I did not try, sorry. When you do a background fsck there is a point at which a snapshot of the filesystem is taken, although I'd say that happens at the beginning of the check. The problem is that with 5.3 Tb, it may take quite a while to take the snapshot, and during that time the system blocks any process that tries to write to the filesystem. Maybe that's what you are experiencing. What you explained us sounds very interesting. But anyway we simply solved by disabling background fsck on such a big partition. We had panics and reboot and we did not want to risk on a production host. Bye Valerio Daelli ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: fsck of big disk
On Tuesday 11 December 2007 09:19:46 am Valerio Daelli wrote: Hi, thanks a lot for your answer. we have a freshly installed FreeBSD 6.2 machine with a gstriped external disk, of 5.3Tb. The disk is composed of two slices of 2.6 Tb. We are trying to have a (background) fsck of it but few hours later since the start of the check the host get unresponsive: it responds to ping but it doesn't let login anyone, nor by ssh nor by console. What do you get if you press Control-T on the console when it is unresponsive? We are not able to login via console nor via ssh. Pheraps you suggest me to press Control-T on the console even if I am not logged on. I did not try, sorry. When you do a background fsck there is a point at which a snapshot of the filesystem is taken, although I'd say that happens at the beginning of the check. The problem is that with 5.3 Tb, it may take quite a while to take the snapshot, and during that time the system blocks any process that tries to write to the filesystem. Maybe that's what you are experiencing. What you explained us sounds very interesting. But anyway we simply solved by disabling background fsck on such a big partition. We had panics and reboot and we did not want to risk on a production host. Bye Valerio Daelli What you are probably running in to is memory starvation. In my experience fsck on a moderately filled disk uses something on the order of 1 gig of RAM per TB of filesystem. If you have this in an array with less than 4 gigs of RAM it's possible that it was just buried in swap and spending all it's time moving pages in and out as opposed to doing anything useful. -- Thanks, Josh Paetzel PGP: 8A48 EF36 5E9F 4EDA 5A8C 11B4 26F9 01F1 27AF AECB signature.asc Description: This is a digitally signed message part.
