From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Hemminger Subject: Re: [PATCH 0/3] eal affinitize low priority threads to lcore 0 Date: Thu, 11 Sep 2014 18:24:24 -0700 Message-ID: <20140911182424.59eb943a@uryu.home.lan> References: <1410445387-4849-1-git-send-email-bruce.richardson@intel.com> <7F861DC0615E0C47A872E6F3C5FCDDBD011AC7A6@BPXM14GP.gisp.nec.co.jp> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: "dev-VfR2kkLFssw@public.gmane.org" To: Hiroshi Shimamoto Return-path: In-Reply-To: <7F861DC0615E0C47A872E6F3C5FCDDBD011AC7A6-ZmjkEB1lVlLt6d3pZDjeaEtBU8KWyXPq@public.gmane.org> List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces-VfR2kkLFssw@public.gmane.org Sender: "dev" On Thu, 11 Sep 2014 23:47:52 +0000 Hiroshi Shimamoto wrote: > Hi Bruce, > > > Subject: [dpdk-dev] [PATCH 0/3] eal affinitize low priority threads to lcore 0 > > > > This patchset sets things up so that we can affinitize the interrupt, > > vfio management, and hpet timer management threads to lcore 0, so that > > they never interfere with data plane threads. > > I don't think it works well always. > The management threads can be floating all cpus on demand, because those > threads are created before the master thread affinity is set. The kernel > scheduler will take care of it. And we should isolate cpus which data plane > threads are pinned to, so the management threads cannot run on those isolated > cpus data plane thread run. > In some cases, the user may run data plane thread on lcore 0, but with > this patchset the data plane pinned to lcore 0 always run with the > management threads. That doesn't seem good. > > I think this functionality should be conditional. > How about to add a parameter to specify the mask for the management threads > instead of statically assignment to lcore 0? > > thanks, > Hiroshi > > > > > Bruce Richardson (3): > > eal: add core id param to eal_thread_set_affinity > > eal: increase scope of eal_thread_set_affinity > > eal: affinitize low-priority threads to lcore 0 > > > > lib/librte_eal/bsdapp/eal/eal_thread.c | 12 ++++++------ > > lib/librte_eal/common/include/eal_private.h | 10 ++++++++++ > > lib/librte_eal/linuxapp/eal/eal_interrupts.c | 5 +++++ > > lib/librte_eal/linuxapp/eal/eal_pci_vfio_mp_sync.c | 6 ++++++ > > lib/librte_eal/linuxapp/eal/eal_thread.c | 12 ++++++------ > > lib/librte_eal/linuxapp/eal/eal_timer.c | 5 +++++ > > 6 files changed, 38 insertions(+), 12 deletions(-) > > > > -- > > 1.9.3 > We just set the non-master DPDK worker threads to be real time by using pthread_set_scheduler. This works very well and makes it clear to Linux scheduler what the intention is. This also improves wakeup behavior from sleeps.