Messages in this thread | | | Date | Thu, 25 Apr 2013 09:49:18 -0400 | From | "" <> | Subject | Re: [PATCH] NFSv4: Use exponential backoff delay for NFS4_ERRDELAY |
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On Thu, Apr 25, 2013 at 01:30:58PM +0000, Myklebust, Trond wrote: > On Thu, 2013-04-25 at 09:29 -0400, bfields@fieldses.org wrote: > > > My position is that we simply have no idea what order of magnitude even > > delay should be. And that in such a situation exponential backoff such > > as implemented in the synchronous case seems the reasonable default as > > it guarantees at worst doubling the delay while still bounding the > > long-term average frequency of retries. > > So we start with a 15 second delay, and then go to 60 seconds?
I agree that a server should normally be doing the wait on its own if the wait would be on the order of an rpc round trip.
So I'd be inclined to start with a delay that was an order of magnitude or two more than a round trip.
And I'd expect NFS isn't common on networks with 1-second latencies.
So the 1/10 second we're using in the synchronous case sounds closer to the right ballpark to me.
--b.
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