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Subj:	Re: WATCHDOG or other packages to kill idle jobs.

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Date: 20 Mar 92 08:21:55 GMT
From: bloom-picayune.mit.edu!mintaka.lcs.mit.edu!olivea!spool.mu.edu!hri.com!merrimack.edu!rand@bloom-beacon.mit.edu
Organization: Merrimack College, No. Andover, MA
Subject: Re: WATCHDOG or other packages to kill idle jobs.
Message-Id: <1992Mar20.082155.1444@merrimack.edu>
References: <01GHK8IAUDU88WWACW@BENTLEY.BITNET>, <1992Mar18.224915.21418@fig.citib.com>, <1992Mar19.211015.7713@eco.twg.com>
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In article <1992Mar19.211015.7713@eco.twg.com>, reece@eco.twg.com (Reece R. Pollack) writes:
> The WATCHDOG program which (is? was?) on the DECUS tapes was largely
> written by George Walrod. One of the problems with a Watchdog type
> program is that by issuing $GETJPI requests to outswapped processes,
> these processes get swapped back in. This results in a lot of churning
> of physical memory contents.
> 
> George decided to fix this problem by going into kernel mode to acquire
> process data. The idea is that queries about outswapped processes can be
> shortcut, thus avoiding in inswap. The problem, of course, is that the
> slightest, most obscure bug tends to crash systems.

Why doesn't George take the easy way out and use jpi$_getjpi_control_flags
jpi$M_no_target_inswap and jpi$M_no_target_ast?

Rand P. Hall, System Janitor, Merrimack College, North Andover, Massachusetts
Internet: rand@merrimack.edu, rand@lucy.merrimack.edu