On Thu, Dec 20, 2018 at 09:40:39AM +0100, Harald Barth wrote: > Have you considered that this could be a problem with TCP packet sizes and > Nagle's algorithm? https://en.wikipedia.org/wiki/Nagle%27s_algorithm > > We have identified back in 2015 that kadmin get * is slow because of > this and I don't thinks that was ever fixed because one needs to > restructure the whole send/receive program flow for this. To start > with one could use TCP_NODELAY and see if that fixes the problem. > > Then if TCP_NODELAY is a permanent fix and should go into the > production code is another question (which was never solved for the > kadmin case if I recall corectly). > > This was just a guess,
It's a pretty good one. The fsync() thing is a big deal by itself. We should definitely make sure we disable Nagle in most TCP protocols in Heimdal. Nico --
