Dickon Hood wrote: > We've got an interesting application which involves recieving lots of > multicast groups, and writing the data to disc as a cache. We're > currently using ZFS for this cache, as we're potentially dealing with a > couple of TB at a time. > > The threads writing to the filesystem have real-time SCHED_FIFO priorities > set to 25. The processes recovering data from the cache and moving it > elsewhere are niced at +10. > > We're seeing the writes stall in favour of the reads. For normal > workloads I can understand the reasons, but I was under the impression > that real-time processes essentially trump all others, and I'm surprised > by this behaviour; I had a dozen or so RT-processes sat waiting for disc > for about 20s.
Are the files opened with O_DSYNC or does the application call fsync ? -- Darren J Moffat _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
