Am Freitag, 24. April 2015, 08:45:15 schrieb Greg Kroah-Hartman: > On Fri, Apr 24, 2015 at 08:36:03AM +0200, Greg Kroah-Hartman wrote: > > On Thu, Apr 23, 2015 at 10:56:40PM +0200, Borislav Petkov wrote: > > > > Hm, this seems to be to be O(1), pretty constant, we do the same > > > > amount > > > > of work all the time. > > > > > > The same *pile* of unnecessary and needless work. You go and collect > > > *all* that data on *every* packet send?! > > > > No, not at all, the metadata is cached, we only collect that for the > > first message sent, if we didn't know it already, or we do it on the > > "open" of the connection, depending on what we are gathering metadata > > for. > > > > The mc->collected test right before collecting the specific metadata > > is > > that "cached or not" test. > > Oh wait, no, there are some send-time metadata that is collected for > every message, see Linus's email for more details about that. Maybe > this can be changed to cache things even more than we currently do. > > it's early, shouldn't write emails before coffee... > > David had some flamegraphs floating around that showed where all the > time on transmit / receive was being spent, and I don't think that the > metadata area was all that relevant, but I can't find them anymore to > say for sure. There are other areas that can be sped up on the send > path, but perf data is the best way to verify this.
I think thats exactly the data that others have asked for several times, so I think it would be good to find it again. -- Martin 'Helios' Steigerwald - http://www.Lichtvoll.de GPG: 03B0 0D6C 0040 0710 4AFA B82F 991B EAAC A599 84C7 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
