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Fellow faulters,

I'm playing around with a one liner that I've developed on a RHEL 5.4 box and I have it working perfectly:

TOTAL_RAM=`free | grep Mem: | awk '{ print $2 }'`; \ 
ps axo rss,comm,pid | awk -v total_ram=$TOTAL_RAM \
'{ proc_list[$2] += $1; } END { for (proc in proc_list) \
{ proc_pct = (proc_list[proc]/total_ram)*100; 
printf("%d\t%s\t%0.2f%\n", proc_list[proc],proc,proc_pct); }}' \
| sort -n | tail -n 10

Which outputs something like the following on my RHEL box:

3736    logmon  0.01%
4156    EvMgrC  0.01%
4692    hald    0.01%
5020    ntpd    0.02%
6252    sshd    0.02%
7784    cvd     0.02%
9224    snmpd   0.03%
13068   dsm_sa_datamgr3 0.04%
23320   dsm_om_connsvc3 0.07%
4249864 mysqld  12.90%

However on my Ubuntu 9.04 slice I get this:

awk: run time error: not enough arguments passed to printf("%d  %s      %0.2f%
        FILENAME="-" FNR=104 NR=104
33248   console-kit-dae 3.17

I think it has to be bash that is borking something, but I'm really not doing anything that should be that bash specific. The RHEL box is running:

# yum info bash | grep -e Version -e Release
Version    : 3.2
Release    : 24.el5

And the Ubuntu box:

# apt-cache show bash | grep -e Version
Version: 3.2-5ubuntu1

I haven't dug into this super deeply, and thought I'd ping my fellow johnnys to see if you've ever run across this before.


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up vote 3 down vote accepted

What does this command show on each system:


and since the error message is being produced by awk, what does this show:

awk --version | head -n 1

In addition to chris's suggestion for escaping the last % in the printf (which can be done with a backslash or by doubling the percent sign), it probably wouldn't hurt to put a line-continuation backslash at the end of the line before the printf.

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So that was it, the RHEL box has GNU Awk 3.1.5 installed. The Ubuntu slice came with mawk which is apparently compatible with GNU Awk except in this Once I installed gawk the script works fine. Thanks for all the help. – d34dh0r53 Mar 26 '10 at 21:52

All I can say, is that it works perfectly fine on my Ubuntu 9.10. But your 4th % sign looks a bit strange to me - as if it relies on some not perfectly specified behaviour. Shouldn't it be escaped?

TOTAL_RAM=`free | grep Mem: | awk '{ print $2 }'`; \ 
ps axo rss,comm,pid | awk -v total_ram=$TOTAL_RAM \
'{ proc_list[$2] += $1; } END { for (proc in proc_list) \
{ proc_pct = (proc_list[proc]/total_ram)*100; 
printf("%d\t%s\t%0.2f%%\n", proc_list[proc],proc,proc_pct); }}' \
| sort -n | tail -n 10
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For completeness (@Dennis): My BASH_VERSION on Ubuntu 9.10 is "4.0.33(1)-release", awk version: "GNU Awk 3.1.6" – Chris Lercher Mar 26 '10 at 21:13
BTW if you escape that last percent sign Awk complains: awk: cmd. line:2: warning: escape sequence \%' treated as plain %' – d34dh0r53 Mar 27 '10 at 0:57
@d34dh0r53: You're right, didn't notice that warning. I changed it to double %, as suggested by Dennis. – Chris Lercher Mar 27 '10 at 1:06

If you're just looking for memory percentage, you can do:

top -b -n1

You'll get some additional info, but it's easier to awk out. Top allows a batch mode such that all of the curses junk isn't piped to other applications.

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