Date: Sat, 27 Aug 2016 01:02:55 +0300 From: Slawa Olhovchenkov <slw@zxy.spb.ru> To: Adrian Chadd <adrian@freebsd.org> Cc: Bruce Simpson <bms@fastmail.net>, Ryan Stone <rysto32@gmail.com>, "svn-src-head@freebsd.org" <svn-src-head@freebsd.org>, Ryan Stone <rstone@freebsd.org>, "src-committers@freebsd.org" <src-committers@freebsd.org>, "svn-src-all@freebsd.org" <svn-src-all@freebsd.org> Subject: Re: svn commit: r304436 - in head: . sys/netinet Message-ID: <20160826220255.GI88122@zxy.spb.ru> In-Reply-To: <CAJ-VmomRDdg5EUUiAHOyVBzitd8cZ8bPGCrU9btnveWeW-_85g@mail.gmail.com> References: <0acba141-4701-d9c2-0ddb-46d1f60ff55b@fastmail.net> <20160820220510.GX8192@zxy.spb.ru> <8ac23bd1-dcb3-7c64-f195-5039f9af0eaf@fastmail.net> <20160821000400.GY8192@zxy.spb.ru> <20160826144926.GE88122@zxy.spb.ru> <3dba1b70-54cc-0bb1-5cc8-8c56cd750bec@fastmail.net> <20160826151324.GF88122@zxy.spb.ru> <CAJ-Vmomg6ejJdZessaUU3DF%2BV%2BsQd=hMZwo_pDYpa4XjoB_ZcA@mail.gmail.com> <20160826213613.GH88122@zxy.spb.ru> <CAJ-VmomRDdg5EUUiAHOyVBzitd8cZ8bPGCrU9btnveWeW-_85g@mail.gmail.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On Fri, Aug 26, 2016 at 02:42:27PM -0700, Adrian Chadd wrote: > On 26 August 2016 at 14:36, Slawa Olhovchenkov <slw@zxy.spb.ru> wrote: > > On Fri, Aug 26, 2016 at 02:32:00PM -0700, Adrian Chadd wrote: > > > >> Hi, > >> > >> It's pcb lock contention. > > > > Not sure: only 5% of all time. > > And same 5% for tcbhashsize = 65K and 256K. > > Or you talk about some more thin effect? > > You're in the inpcb lock from multiple places. For tcp case I am found only 3 places: in_pcbdrop in_pcbremlists in_pcblookup_hash > the tcbhashsize doesnt influence the pcb lock contention - it just > affects how long you take doing lookups. iF your hash table is too > small then you end up doing lots of O(n) walks of a hash bucket to > find a pcb entry. :) Hmm. I am not clearly understund you. How originate pcb lock contention? How I can see this (in pmc profile, in dtarce probese)?
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20160826220255.GI88122>