Infinite loop on bash script and I want to run forever but (I guess) something goes wrong script is killed. Is there any way like try-catch, just continue to running forever, unconditionaly.
#!/bin/bash
iteration=0
for (( ; ; ))
do
process_id=`ps -ef | grep java | grep TEST | awk '{print $2}' `
kill_command='kill -3 '$process_id
time=`date | awk '{print substr($4,0,5)}' `
last_write=`ls -l /files/*.txt | awk '{print $8}' `
if [ "$time" != "$last_write" ]
then
$kill_command
sleep 1
$kill_command
sleep 1
$kill_command
sleep 1
/test/show_queue.sh
fi
let "iteration+=1"
if [ "$iteration" == "30" ]
then
let "iteration=0"
$kill_command
echo '------------' >> memory_status.log
date >> memory_status.log
prstat -n 7 1 1 >> memory_status.log
echo '------------' >> memory_status.log
/test/show_queue.sh
fi
sleep 60
done
A very simple way to do it is to use two scripts. One with the loop and one which does the killing task :
for (( ; ; ))
do
DoKillingTask
rc=$? # <- You get the return code of the script and decide what to do
done
If it continues to be killed, Mikel (in comment of your question) is right.
Related
I want to run a script in the background, and when the time comes bring it back from background and call another script that will take in user input from the command-line, when I use this code, it's able to run the script effectively, but when it calls the other script, it only prints out a couple lines and It isn't able to take in user input, just straight up exits out. Been at it for a couple hours, no idea what to do from here.
I call this script with ./runTool.sh &
currTime=$(ls -lu | grep test01 | awk '{print $8}')
currHour="${currTime:0:2}"
currMin="${currTime:3:3}"
check=0
while [ true ]
do
timestamp=$(ls -lu | grep test01 | awk '{print $8}')
timeHour="${timestamp:0:2}"
timeMin="${timestamp:3:3}"
if (( $timeHour > $currHour )) || (( $timeMin > $currMin )) || (($timeHour < $currHour ))
then
check=1
set -m
fg %1
./tool.sh
break
fi
sleep 1
done
Code sample :
declare -i a=1
echo "The number of NMON instances running in Performance VM"
ps -ef | grep nmon | awk '{ print $2 }' | wc -l
echo "---------------------------------------------"
num2= ps -ef | grep nmon | awk '{ print $2 }' | wc -l
#num1=${num2%%.*}
#num2 = $(ps -ef | grep nmon | awk '{ print $2 }' | wc -l)
echo "---------------------------------------------"
echo "${num2}"
while [ "$a" -lt "$num2" ]
do
kill -USR2 $(ps -ef | grep nmon | awk '{ print $2 }' | head -1)
a=`expr $a + 1`
done
In the Output i am getting the following error
[: : integer expression expected
in the debug it shows
++ '[' 1 -lt '' ']'
that num2 is empty but when i echo the num2 value i am getting the value correctly.
Output:
The number of NMON instances running in Performance VM
1
1
thanks in advance
The 1 you see in the output is not from echo "${num2}". Like the diagnostics already tell you, this variable is empty.
The general syntax of shell scripts is
[ variable=value ...] command parameters ...
which will assign value to variable for the duration of command, then restore its original value. So the pipeline you are running temporarily sets num2 to the empty string (which apparently it already contained anyway), then runs the pipeline without storing the output anywhere (such as, I imagine you expected, in num2).
Here is a fixed version of your script, with the additional change that the Awk scripts handle stuff you used grep and head and wc for. Because the functionality of these commands is easily replaced within Awk, using external utilities is doubtful (especially so for grep which really is useless when you just run it as a preprocessor for a simple Awk script).
countnmon () {
ps -ef | awk '/[n]mon/ { ++n } END { print n }'
}
declare -i a=1
echo "The number of NMON instances running in Performance VM"
countnmon
echo "---------------------------------------------"
num2=$(countnmon)
#num1=${num2%%.*}
#num2 = $(countnmon)
echo "---------------------------------------------"
echo "${num2}"
while [ "$a" -lt "$num2" ]
do
kill -USR2 $(ps -ef | awk '/[n]mon/ { print $2; exit }')
a=`expr $a + 1`
done
The repeated code could be refactored even further to avoid all code duplication but that will somewhat hamper the readability of this simple script so I have not done that.
Whitespaces matter in bash.
The syntax for command execution is:
command arg1 arg2 ...
So,
var = value # command: var, arg1: =, arg2: value
There's are two exceptions to this rule
exporting variables to an executed command (the variables vanish after the command finishes):
var1=value1 var2=value2 .. command arg1 arg2 ...
assigning a variable (you want this one):
var=value
I am trying to run the following shell script, but its exiting without flashing any error ( I am ignoring the program errors but not shell errors).
#!/bin/bash
export TIMEFORMAT="%E"
rm -f mix_histogram
x=1
d=0
while read y
do
d=$(( $(( $d + 1 )) % 2 ))
(time echo '\n' | /home/pallavi/cudaSamples/3_Imaging/histogram 0 >/dev/null 2>/dev /null) > /dev/null 2>> mix_histogram &
t1=$(echo "l(32768)" | bc -l)
t2=$(echo "l(($y))" | bc -l)
t=$(echo "( $t1 - $t2 )" | bc -l)
t=$(echo "( 25 * $t )" | bc -l)
t=$(echo "($t)" | bc)
if [ $(echo "200 < $t"|bc) -eq 1 ]
then
t=200
fi
sleep $t
done < stream1_50
wait
could anybody tell me why its not executing??
How do you know it is not executing?
In such cases, the following is helpful: Run the script this way
bash -x path/to/your/script
This will show an execution trace on standard error.
I have a problem that I can't solve, so I've come to you.
I need to write a program that will read all processes and a program must sort them by users and for each user it must display how much of a memory is used.
For example:
user1: 120MB
user2: 300MB
user3: 50MB
total: 470MB
I was thinking to do this with ps aux command and then get out pid and user with awk command. Then with pmap I just need to get total memory usage of a process.
it's just a little update, users are automatically selected
#!/bin/bash
function mem_per_user {
# take username as only parameter
local user=$1
# get all pid's of a specific user
# you may elaborate the if statement in awk obey your own rules
pids=`ps aux | awk -v username=$user '{if ($1 == username) {print $2}}'`
local totalmem=0
for pid in $pids
do
mem=`pmap $pid | tail -1 | \
awk '{pos = match($2, /([0-9]*)K/, mem); if (pos > 0) print mem[1]}'`
# when variable properly set
if [ ! -z $mem ]
then
totalmem=$(( totalmem + $mem))
fi
done
echo $totalmem
}
total_mem=0
for username in `ps aux | awk '{ print $1 }' | tail -n +2 | sort | uniq`
do
per_user_memory=0
per_user_memory=$(mem_per_user $username)
if [ "$per_user_memory" -gt 0 ]
then
total_mem=$(( $total_mem + $per_user_memory))
echo "$username: $per_user_memory KB"
fi
done
echo "Total: $total_mem KB"
Try this script, which may solve your problem:
#!/bin/bash
function mem_per_user {
# take username as only parameter
local user=$1
# get all pid's of a specific user
# you may elaborate the if statement in awk obey your own rules
pids=`ps aux | awk -v username=$user '{if ($1 == username) {print $2}}'`
local totalmem=0
for pid in $pids
do
mem=`pmap $pid | tail -1 | \
awk '{pos = match($2, /([0-9]*)K/, mem); if (pos > 0) print mem[1]}'`
# when variable properly set
if [ ! -z $mem ]
then
totalmem=$(( totalmem + $mem))
fi
done
echo $totalmem
}
total_mem=0
for i in `seq 1 $#`
do
per_user_memory=0
eval username=\$$i
per_user_memory=$(mem_per_user $username)
total_mem=$(( $total_mem + $per_user_memory))
echo "$username: $per_user_memory KB"
done
echo "Total: $total_mem KB"
Best regards!
You can access the shell commands in python using the subprocess module. It allows you to spawn subprocesses and connect to the out/in/error. You can execute the ps -aux command and parse the output in python.
check out the docs here
Here is my version. I think that Tim's version is not working correctly, the values in KB are too large. I think the RSS column from pmap -x command should be used to give more accurate value. But do note that you can't always get correct values because processes can share memmory. Read this A way to determine a process's "real" memory usage, i.e. private dirty RSS?
#!/bin/bash
if [ "$(id -u)" != "0" ]; then
echo "WARNING: you have to run as root if you want to see all users"
fi
echo "Printing only users that current memmory usage > 0 Kilobytes "
all=0
for username in `ps aux | awk '{ print $1 }' | tail -n +2 | sort | uniq`
do
pids=`ps aux | grep $username | awk -F" " '{print $2}'`
total_memory=0
for pid in $pids
do
process_mem=`pmap -x $pid | tail -1 | awk -F" " '{print $4}'`
if [ ! -z $process_mem ]
then #don't try to add if string has no length
total_memory=$((total_memory+$process_mem))
fi
done
#print only those that use any memmory
if [ $total_memory -gt 0 ]
then
total_memory=$((total_memory/(1024)))
echo "$username : $total_memory MB"
all=$((all+$total_memory))
fi
done
echo "----------------------------------------"
echo "Total: $all MB"
echo "WARNING: Use at your own risk"
i found some freaky error. I want to increment a counter, but the variable isnt visible outside the while do.
The script as follows:
## $1 - The file which should be examined
## $2 - The time passed between the checks. If $2 is 5 then all lines from the last 5 minutes are taken
## $3 - The Errormessage to search for
outputOK="OK - nothing happened"
output_logcheck=0;
errlines="";
cat $1 | grep "$3" | while read line
do
linedate=`date -d "$(echo $line | cut -d " " -f 2)" '+%s'`
nowdate=`date '+%s'`
if [ $(( $nowdate - (60 * $2) )) -le $linedate ]
then
$output_logcheck=$[$output_logcheck+1]
$errlines="${errlines} -- ${line}"
fi
done;
if [ $output_logcheck -eq 0 ]
then
echo $outputOK
else
echo "CRITICAL - There are -= ${output_logcheck} =- $3 -- Lines: $errlines"
fi
So i dont know what else to try.
Thanks in advance.
The problem is that pipe create a SubShell.
change
cat $1 | grep "$3" | while read line
do
...
done
to
while read line
do
...
done <(cat $1 | grep "$3")
As noted, the Bash shell, creates a subshell whenever a pipe is opened to a loop. In that case, variables within the loop are local to the loop.
One kludge is to substitute (if possible) a Korn ('ksh') shell for the Bash one.
Try something like:
## $1 - The file which should be examined
## $2 - The time passed between the checks. If $2 is 5 then all lines from the last 5 minutes are taken
## $3 - The Errormessage to search for
outputOK="OK - nothing happened"
outfile="/tmp/result.$$"
trap { rm $outfile } 0 1 2 3
cat $1 | grep "$3" | (output_logcheck=0; errlines=""; while read line
do
linedate=`date -d "$(echo $line | cut -d " " -f 2)" '+%s'`
nowdate=`date '+%s'`
if [ $(( $nowdate - (60 * $2) )) -le $linedate ]
then
$output_logcheck=$[$output_logcheck+1]
$errlines="${errlines} -- ${line}"
fi
done; echo $output_logcheck ":" $errlines > $outfile)
output_logcheck=`cat $outfile| cut -f1 -d:`
errlines=`cat $outfile|cut -f2 -d:`
if [ $output_logcheck -eq 0 ]
then
echo $outputOK
else
echo "CRITICAL - There are -= ${output_logcheck} =- $3 -- Lines: $errlines"
fi
while is executed in a separate process. Variables that are changed in the context of that process still hold their unchanged valus in the parent process.