On Wed, Nov 9, 2011 at 12:56, Sage Weil <sage@xxxxxxxxxxxx> wrote: > On Tue, 8 Nov 2011, Noah Watkins wrote: > > The only issue with this is that, in the event that you don't guess a > sufficiently large array on the first call, you may need to call again, > and in some cases that may mean multiple MDS requests. Normally that's > not the case. And a smart caller should guess 4 and only pass 0 and then > N if 4 failed. But a naive caller will always make two calls, first with > 0 and then with N, and in some cases that's actually slower. The code I'm using makes a large guess, and an alternative is for the user to cache the replication factor for a file? A similar approach using ERANGE is used by listxattr (well, it communicates ERANGE via errno). In any case, even with Tommi's *naddr_out approach, a certain amount of precise documentation on it's semantics is needed. - Noah -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
