killing a process gone bad.

[Glen Eustace]

We recently had the exact situation described in the previous
posting.  There was a little more code involved but the net effect
was the same.  All attempts to clear out the system failed as there
was no spare CPU available to allow remedial action to be taken.  The
problem was cured by a reboot.

Following our problem, the perpertrator posted to comp.unix.questions
to find out what we could have done.  We received various replies
including the 'kill -9 -1' variety.

I have recently had the oppurunity to repeat the excercise on a
dedicated 3 processor Pyramid MISServer.  After many experiments I
was unable to come up with a satisfactory solution.  My experimental
situation had CPU to spare and the user had consumed all 40 of their
available process table slots.  I still could not clear things up.

NB. The first thing I did was to renice the user to 19 so that all
current processes and any new ones would run as slowly as possible.

It would appear that kill doesn't lock the process table will killing
all of the process group, they still kept replicating.

I would appreciate any further comments by anyone who has a technique
that will actually solve the situation in practice not theory.

-- 
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Glen Eustace, Software Manager, Computer Centre, Massey University,
Palmerston North, New Zealand.        EMail: G.Eustace at massey.ac.nz
Phone: +64 63 69099 x7440, Fax: +64 63 505 607,    Timezone: GMT-12
12

Glen Eustace, Software Manager, Computer Centre, Massey University,
Palmerston North, New Zealand.        EMail: G.Eustace at massey.ac.nz
Phone: +64 63 69099 x7440, Fax: +64 63 505 607,    Timezone: GMT-12
12