Date: Sun, 6 Feb 2000 12:01:10 +0900 (JST) From: amagai@nue.org To: FreeBSD-gnats-submit@freebsd.org Subject: kern/16510: User processes locked on SMP box while burst packet receiving and tcpdumping Message-ID: <200002060301.MAA12968@may.nue.org>
next in thread | raw e-mail | index | archive | help
>Number: 16510
>Category: kern
>Synopsis: User processes locked on SMP box while burst packet receiving and tcpdumping
>Confidential: no
>Severity: critical
>Priority: high
>Responsible: freebsd-bugs
>State: open
>Quarter:
>Keywords:
>Date-Required:
>Class: sw-bug
>Submitter-Id: current-users
>Arrival-Date: Sat Feb 5 19:10:01 PST 2000
>Closed-Date:
>Last-Modified:
>Originator: Y.Amagai
>Release: FreeBSD 3.4-STABLE i386
>Organization:
New Unified Environment Research Project
>Environment:
Host S; PenIII 618M , ASUS P2BF
NIC PLANEX ENW9501 (DEC 21140-A?) 100Base/TX full duplex
single CPU, FreeBSD 2.2.8-Stable
Host D; PenIII 618M * 2 , MB TYAN S1832DL Tiger100
PLANEX ENW9501 (DEC 21140-A?) 100Base/TX full duplex
dual CPU, FreeBSD 3.4-Stable, SMP configured
Host S => 3Com Switch 3300 => Host D
>Description:
on HostS; ping -f -l 5000000 -s 1 hostD >/dev/null
on HostD; tcpdump >/dev/null
No tcpdump running on hostD;
hostD reciving packets about 60000 Packets per Second (pps),
hostS sending packets about 60000 pps
hostD CPU interrupt about 46 % (by /usr/bin/top)
while tcpdump running on hostD;
on HostD, user processes (netstat, top ...) are locked (or are eager for
CPU time silce) .
hostS sending about 80000 pps!!
Kill the ping process on hostS, netstat resume, and reports many input packtes
received.
So, while tcpdump (or packet duplicate in BPF routine), all CPU time
slice may consume in interrupt routines.
Without SMP configuration on hostD, user processes are not locked.
No tcpdump running on hostD;
hostD reciving packets about 46000 pps
hostS sending packets about 46000 pps
hostD CPU interrupt about 60 %
while tcpdump running on hostD;
hostD reciving packets about 44000 pps
hostS sending packets about 44000 pps
hostD CPU interrupt about 60 %
>How-To-Repeat:
as above.
>Fix:
Sorry, I don't know.
>Release-Note:
>Audit-Trail:
>Unformatted:
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-bugs" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200002060301.MAA12968>