Just a quick message to say great work to Neo and any others who have helped with the upgrade - the layout, appearance and functionality of this forum ROCKS.
By far the best I have seen.
Excellent! (1 Reply)
Under, Solaris 10 I have the following problem:
A script executed at command line runs with nice level 0, as expected.
Same script started under (user) crontab runs with nice level 2.
I would prefer it run at 0. Is this possible? If so, how?
Thanks. (0 Replies)
Hi I want to implement the nice command in the shell that I am building. I came to know that there is a corresponding nice() system call for the same. But since I will be forking different processes to run different commands typed on the command prompt, is there any way I can make a command... (2 Replies)
hello everybody:
I have some job running on tru64 system and Im the root, due to limited resources I end up with my job ( vdump) for example taking the lowest share, I researched the nice command on the net, but couldnt get enough info, can I use it to already running process or I only use it... (1 Reply)
Hello,
Some guy said to me that using the nice command to decrease the priority of a process is a myth, that the operating system corrects the priorities as the processes need cpu. Is this true? (4 Replies)
Hello,
I am just starting with shell scripting, as everyone will soon see from my question. What I'm trying to do is call the Nice command to set the script process priority from /bin/ksh. The difference is I'm running it not directly through the shell, but through Bigfix (very similar to... (3 Replies)
Hello Folks,
Recently our FreeBSD 7.1 i386 system became very sluggish.
Nothing much is happening over there & whatever is running takes eternity to complete.
All the troubleshooting hinted towards a very high nice percentage.
Can that be the culprit?
Pasting snippets of top command,... (7 Replies)
with using wall command, how can i have a carriage return in my broadcast message. i try to broadcast from a file, i were to use "cat myfile | wall" for broadcasting. but when the message broadcast somehow the format run away.
this the text in my file:
line 1
line 2
line 3
when broadcast
... (3 Replies)
Discussion started by: lsy
3 Replies
LEARN ABOUT LINUX
ionice
ionice(1) General Commands Manual ionice(1)NAME
ionice - get/set program io scheduling class and priority
SYNOPSIS
ionice [[-c class] [-n classdata] [-t]] -p PID [PID]...
ionice [-c class] [-n classdata] [-t] COMMAND [ARG]...
DESCRIPTION
This program sets or gets the io scheduling class and priority for a program. If no arguments or just -p is given, ionice will query the
current io scheduling class and priority for that process.
As of this writing, a process can be in one of three scheduling classes:
Idle A program running with idle io priority will only get disk time when no other program has asked for disk io for a defined grace
period. The impact of idle io processes on normal system activity should be zero. This scheduling class does not take a priority
argument. Presently, this scheduling class is permitted for an ordinary user (since kernel 2.6.25).
Best effort
This is the effective scheduling class for any process that has not asked for a specific io priority. This class takes a priority
argument from 0-7, with lower number being higher priority. Programs running at the same best effort priority are served in a round-
robin fashion.
Note that before kernel 2.6.26 a process that has not asked for an io priority formally uses "none" as scheduling class, but the io
scheduler will treat such processes as if it were in the best effort class. The priority within the best effort class will be dynam-
ically derived from the cpu nice level of the process: io_priority = (cpu_nice + 20) / 5.
For kernels after 2.6.26 with CFQ io scheduler a process that has not asked for an io priority inherits CPU scheduling class. The
io priority is derived from the cpu nice level of the process (same as before kernel 2.6.26).
Real time
The RT scheduling class is given first access to the disk, regardless of what else is going on in the system. Thus the RT class
needs to be used with some care, as it can starve other processes. As with the best effort class, 8 priority levels are defined
denoting how big a time slice a given process will receive on each scheduling window. This scheduling class is not permitted for an
ordinary (i.e., non-root) user.
OPTIONS -c class
The scheduling class. 0 for none, 1 for real time, 2 for best-effort, 3 for idle.
-n classdata
The scheduling class data. This defines the class data, if the class accepts an argument. For real time and best-effort, 0-7 is
valid data.
-p pid Pass in process PID(s) to view or change already running processes. If this argument is not given, ionice will run the listed pro-
gram with the given parameters.
-t Ignore failure to set requested priority. If COMMAND or PID(s) is specified, run it even in case it was not possible to set desired
scheduling priority, what can happen due to insufficient privileges or old kernel version.
EXAMPLES
# ionice -c 3 -p 89
Sets process with PID 89 as an idle io process.
# ionice -c 2 -n 0 bash
Runs 'bash' as a best-effort program with highest priority.
# ionice -p 89 91
Prints the class and priority of the processes with PID 89 and 91.
NOTES
Linux supports io scheduling priorities and classes since 2.6.13 with the CFQ io scheduler.
AUTHORS
Jens Axboe <jens@axboe.dk>
AVAILABILITY
The ionice command is part of the util-linux package and is available from ftp://ftp.kernel.org/pub/linux/utils/util-linux/.
ionice August 2005 ionice(1)