Date: Thu, 09 May 2013 21:55:42 +0700 From: Eugene Grosbein <egrosbein@rdtc.ru> To: =?UTF-8?B?IkNsw6ltZW50IEhlcm1hbm4gKG5vZGVucyki?= <nodens2099@gmail.com> Cc: freebsd-net@freebsd.org Subject: Re: High CPU interrupt load on intel I350T4 with igb on 8.3 Message-ID: <518BB8EE.2080705@rdtc.ru> In-Reply-To: <517A657B.7060003@gmail.com> References: <517A657B.7060003@gmail.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On 26.04.2013 18:31, "Clément Hermann (nodens)" wrote: > Hi list, > > We use pf+ALTQ for trafic shaping on some routers. > > We are switching to new servers : Dell PowerEdge R620 with 2 8-cores > Intel Processor (E5-2650L), 8GB RAM and Intel I350T4 (quad port) using > igb driver. The old hardware is using em driver, the CPU load is high > but mostly due to kernel and a large pf ruleset. > > On the new hardware, we see high CPU Interrupt load (up to 95%), even > though there is not much trafic currently (peaks about 150Mbps and > 40Kpps). All queues are used and binded to a cpu according to top, but a > lot of CPU time is spent on igb queues (interrupt or wait). The load is > fine when we stay below 20Kpps. > > We see no mbuf shortage, no dropped packet, but there is little margin > left on CPU time (about 25% idle at best, most of CPU time is spent on > interrupts), which is disturbing. It seems you suffer from pf lock contention. You should stop using pf with multi-core systems with 8.3. Move to ipfw+dummynet or ng_car for 8.3 or move to 10.0-CURRENT having new, rewritten pf that does not have this problem. Network device driver is not guilty here, that's just pf's contention running in igb's context. Eugene Grosbein
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?518BB8EE.2080705>