Bug 14932
| Summary: | "more" eating up CPU on users with shell=/bin/sh if telnetd disconnects | ||
|---|---|---|---|
| Product: | Base System | Reporter: | bruce <bruce> |
| Component: | misc | Assignee: | freebsd-bugs (Nobody) <bugs> |
| Status: | Closed FIXED | ||
| Severity: | Affects Only Me | ||
| Priority: | Normal | ||
| Version: | Unspecified | ||
| Hardware: | Any | ||
| OS: | Any | ||
|
Description
bruce
1999-11-17 01:30:00 UTC
On Tue, 16 Nov 1999 17:26:16 PST, bruce@engmail.uwaterloo.ca wrote: > On 3.3 RELEASE, on a user with login shell of /bin/sh, if a user > runs "more /etc/passwd" (or something) and then has their /bin/sh > or telnetd killed (either manually with kill -9 or if the telnetd > keepalive mechanism terminates a disconnected connection) "more" > starts spinning, and quickly goes to the top of "top", eating 50% CPU > or more Hi Bruce, As per my message sent earlier, please test with with 3.3-STABLE. I can't reproduce the problem with 3.3-STABLE, and if a problem in 3.3-RELEASE doesn't exist in 3.3-STABLE, there's nothing we can do about it now. Also, note that the problem is not that more "eats up CPU" -- I'm pretty sure it's just spinning on input, so if the system got busier, you'd probably find that the CPU usage of the more processes would flatten out. The problem is simply that the children of the shell process should die when you kill the shell. Ciao, Sheldon. The problem persists on 3.3 STABLE from Nov 17. Our e-mail server, which is heavily loaded regularly (load average 5-10 quite often), is pushed over the edge once a few "more" processes start spinning, and the load average can climb to 20 or 30, rendering the e-mail server unuseable for all practical purposes. On our test machine that we upgraded to 3.3 STABLE, the source for /bin/sh is unchanged from 3.3 RELEASE. The source for /usr/bin/more has a number of changed files on Nov 17. Results on test machine... # uname -a FreeBSD elsinore.uwaterloo.ca 3.3-STABLE FreeBSD 3.3-STABLE #0: Thu Nov 18 13:36:03 EST 1999 root@elsinore.uwaterloo.ca:/usr/src/sys/compile/ELSINORE i386 # ps waux | grep junk root 11183 0.0 1.3 876 380 p6 D+ 1:03PM 0:00.01 grep junk junk 11177 0.0 0.9 500 256 p5 Ss 1:02PM 0:00.03 -sh (sh) junk 11178 0.0 1.8 860 508 p5 S+ 1:02PM 0:00.01 more /etc/passwd # kill -KILL 11177 # !ps ps waux | grep junk junk 11178 7.1 1.7 860 492 p5- R 1:02PM 0:01.61 more /etc/passwd # "top" outout... PID USERNAME PRI NICE SIZE RES STATE TIME WCPU CPU COMMAND 11178 junk 100 0 860K 492K RUN 7:21 98.97% 98.97% more On Tue, Nov 16, 1999 at 05:26:16PM -0800, bruce@engmail.uwaterloo.ca wrote: > > >Description: > On 3.3 RELEASE, on a user with login shell of /bin/sh, > if a user runs "more /etc/passwd" (or something) and then > has their /bin/sh or telnetd killed (either manually with > kill -9 or if the telnetd keepalive mechanism terminates a > disconnected connection) "more" starts spinning, and quickly goes to > the top of "top", eating 50% CPU or more I've fixed more to exit after it reads two EOFs, but the more serious problem here, of course, is that /bin/sh isn't propogating signals correctly. The updated more is in -current and 4-stable. I'm not sure if I'll merge it all the way back to 3-stable unless you need it there. Being from the evil university, you'd have to ask really really nicely... ;-) -- Signature withheld by request of author. State Changed From-To: open->closed Appears fixed in all current versions of FreeBSD. |
