> On Fri, 14 Nov 2003, Rob Siemborski wrote: > > > On Fri, 14 Nov 2003, Simon Matter wrote: > > > > > IIRC taking a snapshot with LVM/XFS takes just a few seconds. I guess > > > everything should continue after the snapshot. What do the cyrus processes > > > do if they receive SIGSTOP? Will they stop immediately or will they not > > > stop at all? I mean, if a process receives SIGSTOP while it writes to a > > > file, will the write finish before the process stops? > > > > I'm pretty sure if you just stop the processes where they are, you'll > > still get an inconsistent store. (E.g. the mail file is written out, but > > the index files aren't yet updated). > > As I think about this further -- it might be possible to somehow signal to > all of the cyrus processes that they need to reach a quiescent state, but > I suspect that doing this to the point of absolute consistency may be > significantly time consuming, as you may find yourself waiting for network > operations to complete also. > > I don't think the work to even get to that point is trivial however. >
Hi all, Rob, I'm still abit confused about what's needed to get cyrus (including index files) into a consistent state -- ready for a backup/snapshot.. etc. etc. -jim
