On Thu, 29 Oct 2015, Yan, Zheng wrote: > On Thu, Oct 29, 2015 at 2:21 PM, Gregory Farnum <gfarnum@xxxxxxxxxx> wrote: > > On Wed, Oct 28, 2015 at 8:38 PM, Yan, Zheng <ukernel@xxxxxxxxx> wrote: > >> On Thu, Oct 29, 2015 at 1:10 AM, Burkhard Linke > >>> I tried to dig into the ceph-fuse code, but I was unable to find the > >>> fragment that is responsible for flushing the data from the page cache. > >>> > >> > >> fuse kernel code invalidates page cache on opening file. you can > >> disable this behaviour by setting ""fuse use invalidate cb" config > >> option to true. > > > > Zheng, do you know any reason we shouldn't make that the default value > > now? There was a loopback deadlock (which is why it's disabled by > > default) but I don't remember the details offhand well enough to know > > if your recent work in those interfaces has fixed it. Or Sage? > > -Greg > > there is no loopback deadlock now, because we use a separate thread to > invalidate kernel page cache. I think we can enable this option > safely. ...as long as nobody blocks waiting for invalidate while holding a lock (client_lock?) that could prevent other fuse ops like write (pretty sure that was the deadlock we saw before). I worry this could still happen with a writer (or reader?) getting stuck in a check_caps() type situation while the invalidate cb is waiting on a page lock held by the calling kernel syscall... sage _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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