hi,
i want to know cpu utilizatiion per process per cpu..for single processor also if multicore in linux ..to use these values in shell script to kill processes exceeding cpu utilization.ps (pcpu) command does not give exact values..top does not give persistant values..psstat,vmstat..does njot... (3 Replies)
Hello Friends,
On one of my Solaris 10 box, CPU usage shows 100% using "sar", "vmstat". However, it has 4 CPUs and prstat and glance are not showing enough processes to justify high CPU utilization.
=========================================================================
$ prstat -a
... (4 Replies)
Hi,
We have a filesystem mystery on our hands. Given:
2 machines, A and Aa.
Machine Aa is the problem machine.
Machine A is running Ubuntu, kernel 2.6.22.9 #1 SMP Wed Feb 20 08:46:16 CST 2008 x86_64 GNU/Linux. Machine Aa is running RHEL5.3, kernel 2.6.18-128.el5 #1 SMP Wed Dec 17 11:41:38... (2 Replies)
Hi,
We have smb client running on two of the linux boxes and smb server on another linux system. During a backup operation which uses smb, read of a file was allowed while write to the same file was going on.Also simultaneous writes to the same file were allowed.Following are the settings in the... (1 Reply)
Hi guys,
I wrote a basic inotifywait shell script on my CentOS 5.6 x86_64 test server that syncs any deleted files in a directory.
/usr/bin/script
#!/bin/sh
inotifywait -m -e delete /home/user/test | while read file; do
# log event here
done
The script alone works fine. However, the... (4 Replies)
I have a set of requirement
1)cpu utilization on a server with pid and and process name.
It should display the above and also the script should have an option to record the cpu utilization for a given period of time
first part i can get with below commands
ps -eo pcpu,pid,user,args or... (5 Replies)
Hi All,
I have a script which does report the cpu usuage, there are few output parameter/fields displayed from the script. My problem is I have monitor the output and decide
which cpu number (column 2) has maximum value (column 6).
Since the output is displayed/updated every seconds, it's very... (1 Reply)
Hello Friends,
I am trying to create a shell script which will check the CPU utilization. I use command top to check the %CPU usage. It give s me below output
Cpu states:
CPU LOAD USER NICE SYS IDLE BLOCK SWAIT INTR SSYS
0 0.31 9.6% 0.0% 6.1% 84.3% 0.0% 0.0%... (3 Replies)
We have a single threaded application which is restricted by CPU usage even though there are multiple CPUs on the server, hence leading to significant performance issues. Is it possible to merge / combine multiple CPUs at OS level so it appear as a single CPU for the application? (6 Replies)
Hello experts,
we have input files with 700K lines each (one generated for every hour). and we need to convert them as below and move them to another directory once.
Sample INPUT:-
# cat test1
1559205600000,8474,NormalizedPortInfo,PctDiscards,0.0,Interface,BG-CTA-AX1.test.com,Vl111... (7 Replies)
Discussion started by: prvnrk
7 Replies
LEARN ABOUT OPENDARWIN
urandom
RANDOM(4) BSD Kernel Interfaces Manual RANDOM(4)NAME
random , urandom -- random data source devices.
SYNOPSIS
pseudo-device random
DESCRIPTION
The random device produces uniformly distributed random byte values of potentially high quality.
To obtain random bytes, open /dev/random for reading and read from it.
To add entropy to the random generation system, open /dev/random for writing and write data that you believe to be somehow random.
/dev/urandom is a compatibility nod to Linux. On Linux, /dev/urandom will produce lower quality output if the entropy pool drains, while
/dev/random will prefer to block and wait for additional entropy to be collected. With Yarrow, this choice and distinction is not necessary,
and the two devices behave identically. You may use either.
OPERATION
The random device implements the Yarrow pseudo random number generator algorithm and maintains its entropy pool. Addditional entropy is fed
to the generator regularly by the SecurityServer daemon from random jitter measurements of the kernel. SecurityServer is also responsible
for periodically saving some entropy to disk and reloading it during startup to provide entropy in early system operation.
You may feed additional entropy to the generator by writing it to the random device, though this is not required in a normal operating envi-
ronment.
LIMITATIONS AND WARNINGS
Yarrow is a fairly resilient algorithm, and is believed to be resistant to non-root. The quality of its output is however dependent on regu-
lar addition of appropriate entropy. If the SecurityServer system daemon fails for any reason, output quality will suffer over time without
any explicit indication from the random device itself.
Paranoid programmers can counter-act this risk somewhat by collecting entropy of their choice (e.g. from keystroke or mouse timings) and
seeding it into random directly before obtaining important random numbers.
FILES
/dev/random
/dev/urandom
HISTORY
A random device appeared in Linux operating system.
Darwin September 6, 2001 Darwin