I'm using the term "rotate" loosely.  Unlike other log files, which prune
older contents based on size and age, when the dsminstr.log reaches the
configured maximum size, the file is renamed to dsminstr.log.bak and a new
log is created.

At least on RHEL 6.8, the dsmc command that triggers the rotation crashes
with a glibc "double free or corruption" error.  Further, if the user running
that dsmc command can't rename the file (e.g. the file is root-owned and mode
666, and in /var/tmp or similar with the sticky bit set, but dsmc is running
as another user), the dsmc crash happens every time until the file is renamed
(manually or by a dsmc run by a user with rights to rename it).

Not sure if I explained that clearly or not.  To reproduce the crash itself
(in a timely manner), set "INSTRLOGMAX 1" so the rename happens sooner, then
run enough dsmc activity to generate 1 MB of instrumentation data and trigger
the log renaming.

Also, the INSTRLOGMAX documentation seems contradictory.  It says if you
don't specify the option, the log can grow without limit, but later it says
the default value is 25 MB (which seems to be correct).

=Dave


On 07/13/2016 01:30 PM, Andrew Raibeck wrote:
> Hi David,
>
> What is this "rotating" of logs you refer to? Is this related to log
> retention and pruning?
>
> dsminstr.log is managed in a fashion similar to dsmerror.log with regard to
> user permissions and file locking. Is this causing a problem? Or are you
> just making an observation?
>
> Yes, please open a PMR. But if you can elaborate on these issues (how we
> can try to reproduce them), I can forward them to the appropriate
> developer, then hopefully meet in the middle regarding the PMR.
>
> Regards,
>
> Andy
>
>
>> From: David Bronder <david-bronder AT UIOWA DOT EDU>
>> To: ADSM-L AT VM.MARIST DOT EDU
>> Date: 2016-07-13 13:59
>> Subject: Re: 7.1.6 client default changed?
>> Sent by: "ADSM: Dist Stor Manager" <ADSM-L AT VM.MARIST DOT EDU>
>>
>> Yes, they turned it on by default in 7.1.6 and changed configuration from
> a
>> testflag to a new option (ENABLEINSTRUMENTATION):
>>
>>
>> https://www.ibm.com/support/knowledgecenter/SSGSG7_7.1.6/client/
>> r_new_for_version.html
>>
>> One more pain point when supporting client operations for non-root users
> (log
>> file permissions and a lock file).  Plus, I need to open a PMR about a
>> dsmc/glibc crash when it tries to rotate the dsminstr.log file.
>>
>>
>> On 07/13/2016 12:32 PM, Lee, Gary wrote:
>>> Tsm client 7.1.6
>>> Os rhel 6.8
>>> Tsm server 6.3.4
>>>
>>> Looks like client instrumentation is defaulted to on.
>>> Is this new?
>>>
>>> No flags in my dsm.opt or dsm.sys.
>>>
>>

--
Hello World.                                David Bronder - Systems Architect
Segmentation Fault                                      ITS-EI, Univ. of Iowa
Core dumped, disk trashed, quota filled, soda warm.   david-bronder AT uiowa 
DOT edu