Re: tgtadm/tgtd management issue: buffer size truncated sometimes

On Fri, 24 Jan 2014 12:51:13 +0400
Artyom Pervukhin <[email protected]> wrote:

> Can you please specify what linux distribution and libraries version
> are you using?

Debian squeeze amd64.

> I¢m able to reproduce this bug on current tgt codebase (17222f2b00d29368da214e2d59cbc9e00f53606b) built on  Debian wheezy amd64. Bug frequency increases with number of targets:
> 
> 
> 1000 targets (all loaded, as `tgtadm -C 0 --op show --mode target --tid 1000` shows target settings):
> 
> root@sandbox:~ # for i in $(seq 100) ; do tgtadm -C 0 --op show --mode target | grep -c ^Target ; done | sort | uniq -c                                                     
>     100 978
> root@sandbox:~ # for i in $(seq 100) ; do tgtadm -C 0 --op show --mode target | wc -c ; done | sort | uniq -c                                                              
>     100 1033140

I can reproduce the same problem with 1000.

root@rose:~# for i in $(seq 100); do tgtadm --op show --mode target|grep -c ^Target;done|sort|uniq -c
     97 1000
      1 972
      1 995
      1 997

Strangely, looks like I can get the correct result without 'grep':

root@rose:~# for i in $(seq 100); do tgtadm --op show --mode target|python -c "import sys; print len([line for line in sys.stdin if \"Target\" in line])";done|sort|uniq -c
    100 1000