2008/5/28 Oliver Fromme <[EMAIL PROTECTED]>: > Ivan Voras wrote: > > Im thinking again of the old idea of implementing poor man's file > > replication system using kqueue to monitor changes on files. > > It would be cool to have a kernel interface so you could > attach to a mountpoint and receive a log of all activity > on that file system. That's similar to what DragonFly's > journaling feature does.
/me agrees. > Unfortunately the kqueue interface isn't capable of doing > something like that ... So this is not an answer to your > question, I'm afraid. > > > One other question: do kqueue events "coalesce" in the sense that if N > > operations happen (like write()s), there can be < N events passed to the > > kqueue (NOTE_WRITE)? > > The manpage says: "Multiple events which trigger the filter > do not result in multiple kevents being placed on the kqueue; > instead, the filter will aggregate the events into a single > struct kevent." That's mildly unfortunate but I think you're right - it agrees with the statement from the kqueue paper: "Events will normally considered to be "level-triggered", as opposed to "edge-triggered"." > > While at it, will EVFILT_VNODE and NOTE_WRITE catch "additional" ways > > the file can be modified, meaning mmap()? > > A quick grep for NOTE_WRITE on the sys tree indicates that > it doesn't. I'm not 100% sure though. Also bad for some users. _______________________________________________ freebsd-hackers@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "[EMAIL PROTECTED]"
