On Wed, 2006-06-21 at 14:15, Neil Perrin wrote: > Of course we would need to stress the dangers of setting 'deferred'. > What do you guys think?
I can think of a use case for "deferred": improving the efficiency of a large mega-"transaction"/batch job such as a nightly build. You create an initially empty or cloned dedicated filesystem for the build, and start it off, and won't look inside until it completes. If the build machine crashes in the middle of the build you're going to nuke it all and start over because that's lower risk than assuming you can pick up where it left off. now, it happens that a bunch of tools used during a build invoke fsync. But in the context of a full nightly build that effort is wasted. All you need is one big "sync everything" at the very end, either by using a command like sync or lockfs -f, or as a side effect of reverting from sync=deferred to sync=standard. - Bill _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss