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to 老农:各位老大帮忙分析一下系统性能 RS 6000 IBM M80
不知道这个对于 CPU Time Limit有没有用?
Cpu time limit
Revised: February 2001
Cpu time limit
Each account is set up with a default limit for the maximum amount
of processor time a task may use. If a task runs over the limit
it is terminated with the message
Cputime limit exceeded
The purpose of the limit is to prevent background tasks which are
left running after logout from inadvertently running "forever".
Some tasks may legitimately require more cpu time than the default
limit.
AD HOC CPU LIMIT ADJUSTMENTS
A temporary limit change may be made by typing at the shell (%)
cpulimit 3600
Note that the "cpulimit" command is an alias defined either in your
.cshrc file or in /public/cshrc.adjunct which is sourced by your
.cshrc file. If you get "cpulimit: Command not found", you can add
this alias to your .cshrc file and then re-login,
alias cpulimit 'setenv CPU \!*; limit cpu $CPU'
"cpulimit 3600" limits subsequent tasks, in the current session,
making sure they do not individually exceed 3600 seconds of processor
time.
The cpu limit can be turned off altogether (not a very good idea unless
you are certain that you do not have a runaway job) by typing at the
shell (%)
unlimit cpu
CHANGING THE DEFAULT CPU LIMIT
You can change the default cpu limit for your account by adding
a line like "cpulimit 3600" to the *end* of your .login and .cshrc
files. [Actually only one or the other is necessary, but putting
the command both places will save you the trouble of figuring out
which one is appropriate for your system.]
Instructors or TAs can modify the cpu limit for all the students in a
class. The technique depends on the system type and whether or not
the course is set up using the OCE model. You may want to seek
assistance from ACS ( acs-consult.ucsd.edu ), but briefly, if the
the course is using the OCE model, put the cpulimit command
(e.g. "cpulimit 3600" in the prepfile for the course. Otherwise
the cpulimit command needs to be placed in the locallogin or localcshrc
file for the course, depending on the system type. Putting it in both
will do the job and should not cause any problems.
AVOIDING PROBLEMS WITH CPU LIMIT WHEN EDITING
It is painful to have an editing session terminate due to the cputime
limit, particularly if you are in visual mode. The terminal is left in
a strange state where characters are not echoed, and the LINEFEED key
must be used instead of RETURN. If you ever "bomb" out of visual, try
typing LINEFEED reset LINEFEED.
To avoid the possibility of running out of cpu time while editing, most
accounts have an alias specified for vi which temporarily unlimits cpu
time during visual editing sessions. See /public/cshrc for an example
of such an alias.
For more information regarding the command "limit" see "man csh". |
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