On Tue, 8 Mar 2016 10:50:56 +0100 Jesper Dangaard Brouer <jbro...@redhat.com> wrote:
> On Mon, 7 Mar 2016 12:54:13 -0500 > Willem de Bruijn <willemdebruijn.ker...@gmail.com> wrote: > > > On Mon, Mar 7, 2016 at 10:36 AM, Jesper Dangaard Brouer > > <jbro...@redhat.com> wrote: > > > Hi Google, > > > > > > While playing with RPS, I needed to read stats from > > > /proc/net/softnet_stat and the tools I could find [1] and [2] was not > > > very good. > > > > > > I lack of better, I coded up my own tool softnet_stat.pl here: > > > > > > https://github.com/netoptimizer/network-testing/blob/master/bin/softnet_stat.pl > > > > > > The output format/columns in /proc/net/softnet_stat is undocumented, > > > plus values are printed in hex. E.g. to decode the columns you need to > > > read kernel function kernel softnet_seq_show() in > > > kernel/net/core/net-procfs.c. > > > > > > To make things easier I wrote this small perl script for get > > > so human readable statistics from /proc/net/softnet_stat. > > > > Very nice. Thanks for sharing, Jesper. I maintained something similar, > > but never got around to clean up and upstream it. Will start using > > yours, instead. > > > > A few points, from using my earlier tool: > > > > A minimum cut-off value is helpful, especially on beefy servers, to > > suppress the many 0 rows. Preferably configurable, to also be able to > > suppress low-rate background traffic when analyzing a few large > > streams. My default was 500. > > > > The number of columns has grown with kernel versions. The latest > > column is flow_limit, added in 3.11 at99bbc7074190. It is helpful for > > the script to be robust against both older and future kernels. On > > which note, to be able to support these kinds of tools, any new > > columns to such procfs files should be appended, not inserted as for > > instance in https://patchwork.ozlabs.org/patch/574171/ > > > > Time squeeze is an exception, in that it is number of squeeze events > > per second, not number of packets squeezed. This is often > > misunderstood if not explained clearly. > > Thanks a lot for your feedback. I don't have time to address it right > away, so I've instead added a section with future development todo's. > So, I don't forget this valuable feedback :-) > > https://github.com/netoptimizer/network-testing/commit/c464676e456aab Found a bug in my script: https://github.com/netoptimizer/network-testing/blob/master/bin/softnet_stat.pl It was not showing the "squeezed" events. It is now fixed: https://github.com/netoptimizer/network-testing/commit/3b5ca843cf -- Best regards, Jesper Dangaard Brouer MSc.CS, Principal Kernel Engineer at Red Hat Author of http://www.iptv-analyzer.org LinkedIn: http://www.linkedin.com/in/brouer
