From owner-freebsd-current Thu Jun 4 15:29:24 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id PAA23650 for freebsd-current-outgoing; Thu, 4 Jun 1998 15:29:24 -0700 (PDT) (envelope-from owner-freebsd-current@FreeBSD.ORG) Received: from godzilla.zeta.org.au (godzilla.zeta.org.au [203.15.68.22]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id PAA23603 for ; Thu, 4 Jun 1998 15:29:15 -0700 (PDT) (envelope-from bde@godzilla.zeta.org.au) Received: (from bde@localhost) by godzilla.zeta.org.au (8.8.7/8.8.7) id IAA23654; Fri, 5 Jun 1998 08:29:11 +1000 Date: Fri, 5 Jun 1998 08:29:11 +1000 From: Bruce Evans Message-Id: <199806042229.IAA23654@godzilla.zeta.org.au> To: current@FreeBSD.ORG, straka@home.com Subject: Re: strange behavior with signal latencies Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG >In looking at the results, I noticed that that the current box exhibited >a 2300 microsecond additional delay every 10th signal or at 100ms >intervals. Also, occationally a signal is missed. I have also noticed >recently using top and systat that current has been consuming between >1.6% and 3.1% of my P133 in interrupt handling. This seems to >correspond to the latancy I am seeing with the signal test code. I >changed the quantum interval using sysctl to 20 ticks. This had no >effect, the 2300 microsecond latency still appeared at 10Hz. > >The results with 2.2.6R on the 486-100 box showed no signs of the >latency and appeared to always reliably wakeup on every signal. Also, >when the machine is completely idle, the interrupt load is 0.0%, >occationally jumping to 0.4% when the disks sync. The results show no signs of latency with -current on a P5/133 here. This should be relatively easy to debug - just find whatever is causing the abnormal interrupt load. I suspect it is an interrupt handler looping. Bruce To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message