On 12/05/15 01:18, Paul Emmerich wrote: > Found a really simple solution that almost restores the original > performance: just add a prefetch on alloc. For some reason, I assumed > that this was already done since the troublesome commit I investigated > mentioned something about prefetching... I guess the commit referred > to the hardware prefetcher in the CPU. > > Adding an explicit prefetch command in the mbuf alloc function gives a > throughput of 12.7/10.35 Mpps in my benchmark with the > simple/full-featured tx path. > > DPDK 1.7.1 was at 14.1/10.7 Mpps. I guess I can live with that, since > I'm primarily interested in the full-featured path and the drop from > 10.7 to ~10.4 was due to another change.
Maybe a stupid question; Does the performance of v1.7.1 also improve if you backport this patch to it? Marc > > Patch: https://github.com/dpdk-org/dpdk/pull/2 > I also sent an email to the mailing list. > > I also think that the rx-path could also benefit from prefetching > somewhere. > > > Paul >