NICELOAD(1) parallel NICELOAD(1)NAMEniceload - slow down a program when the load average is above a certain
limit
SYNOPSISniceload [-v] [-h] [-n nice] [-I io] [-L load] [-M mem] [-N] [--sensor
program] [-t time] [-s time|-f factor] ( command | -p PID [-p PID ...]
)
DESCRIPTION
GNU niceload will slow down a program when the load average (or other
system activity) is above a certain limit. When the limit is reached
the program will be suspended for some time. Then resumed again for
some time. Then the load average is checked again and we start over.
Instead of load average niceload can also look at disk I/O, amount of
free memory, or swapping activity.
If the load is 3.00 then the default settings will run a program like
this:
run 1 second, suspend (3.00-1.00) seconds, run 1 second, suspend
(3.00-1.00) seconds, run 1 second, ...
OPTIONS-f FACTOR
--factor FACTOR
Suspend time factor. Dynamically set -s as amount over limit *
factor. Default is 1.
-H
--hard Hard limit. --hard will suspend the process until the system
is under the limits. The default is --soft.
--io iolimit
-I iolimit
Limit for I/O. The amount of disk I/O will be computed as a
value 0 - 10, where 0 is no I/O and 10 is at least one disk is
100% saturated.
--io will set both --start-io and run-io.
--load loadlimit
-L loadlimit
Limit for load average.
--load will set both --start-load and run-load.
--mem memlimit
-M memlimit
Limit for free memory. This is the amount of bytes available
as free + cache. This limit is treated opposite other limits:
If the system is above the limit the program will run, if it
is below the limit the program will stop
memlimit can be postfixed with K, M, G, T, or P which would
multiply the size with 1024, 1048576, 1073741824, or
1099511627776 respectively.
--mem will set both --start-mem and run-mem.
--noswap
-N No swapping. If the system is swapping both in and out it is a
good indication that the system is memory stressed.
--noswap is over limit if the system is swapping both in and
out.
--noswap will set both --start-noswap and run-noswap.
-n niceness
--nice niceness
Sets niceness. See nice(1).
-p PID (alpha testing)
--pid PID (alpha testing)
Process ID of process to suspend. You can specify multiple
process IDs with multiple -p PID.
--prg program (alpha testing)
--program program (alpha testing)
Name of running program to suspend. You can specify multiple
programs with multiple --prg program.
--quote
-q Quote the command line. Useful if the command contains chars
like *, $, >, and " that should not be interpreted by the
shell.
--run-io iolimit
--ri iolimit
--run-load loadlimit
--rl loadlimit
--run-mem memlimit
--rm memlimit
Run limit. The running program will be slowed down if the
system is above the limit. See: --io, --load, --mem, --noswap.
--sensor sensor program (alpha testing)
Read sensor. Use sensor program to read a sensor.
This will keep the CPU temperature below 80 deg C on
GNU/Linux:
niceload-l 80000 -f 0.001 --sensor 'sort -n /sys/devices/platform/coretemp*/temp*_input' gzip *
This will stop if the disk space < 100000.
niceload-H -l -100000 --sensor "df . | awk '{ print \$4 }'" echo
--start-io iolimit
--si iolimit
--start-load loadlimit
--sl loadlimit
--start-mem memlimit
--sm memlimit
Start limit. The program will not start until the system is
below the limit. See: --io, --load, --mem, --noswap.
--soft
-S Soft limit. niceload will suspend a process for a while and
then let it run for a second thus only slowing down a process
while the system is over one of the given limits. This is the
default.
--suspend SEC
-s SEC Suspend time. Suspend the command this many seconds when the
max load average is reached.
--recheck SEC
-t SEC Recheck load time. Sleep SEC seconds before checking load
again. Default is 1 second.
--verbose
-v Verbose. Print some extra output on what is happening. Use -v
until you know what your are doing.
EXAMPLE: See niceload in action
In terminal 1 run: top
In terminal 2 run:
niceload-q perl -e '$|=1;do{$l==$r or print ".";
$l=$r}until(($r=time-$^T)>50)'
This will print a '.' every second for 50 seconds and eat a lot of CPU.
When the load rises to 1.0 the process is suspended.
EXAMPLE: Run updatedb
Running updatedb can often starve the system for disk I/O and thus
result in a high load.
Run updatedb but suspend updatedb if the load is above 2.00:
niceload-L 2 updatedb
EXAMPLE: Run rsync
rsync can just like updatedb starve the system for disk I/O and thus
result in a high load.
Run rsync but keep load below 3.4. If load reaches 7 sleep for
(7-3.4)*12 seconds:
niceload-L 3.4 -f 12 rsync -Ha /home/ /backup/home/
EXAMPLE: Ensure enough disk cache
Assume the program foo uses 2 GB files intensively. foo will run fast
if the files are in disk cache and be slow as a crawl if they are not
in the cache.
To ensure 2 GB are reserved for disk cache run:
niceload--hard --run-mem 2g foo
This will not guarantee that the 2 GB memory will be used for the files
for foo, but it will stop foo if the memory for disk cache is too low.
ENVIRONMENT VARIABLES
None. In future versions $NICELOAD will be able to contain default
settings.
EXIT STATUS
Exit status should be the same as the command being run (untested).
REPORTING BUGS
Report bugs to <bug-parallel@gnu.org>.
AUTHOR
Copyright (C) 2004-11-19 Ole Tange, http://ole.tange.dk
Copyright (C) 2005,2006,2006,2008,2009,2010 Ole Tange,
http://ole.tange.dk
Copyright (C) 2010,2011,2012 Ole Tange, http://ole.tange.dk and Free
Software Foundation, Inc.
LICENSE
Copyright (C) 2010,2011,2012 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 3 of the License, or at your
option any later version.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License along
with this program. If not, see <http://www.gnu.org/licenses/>.
Documentation license I
Permission is granted to copy, distribute and/or modify this
documentation under the terms of the GNU Free Documentation License,
Version 1.3 or any later version published by the Free Software
Foundation; with no Invariant Sections, with no Front-Cover Texts, and
with no Back-Cover Texts. A copy of the license is included in the
file fdl.txt.
Documentation license II
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DEPENDENCIES
GNU niceload uses Perl, and the Perl modules POSIX, and Getopt::Long.
SEE ALSOparallel(1), nice(1), uptime(1)20140522 2013-08-15 NICELOAD(1)
