Proc entry to know task/thread sleep time

Proc entry to know task/thread sleep time

[Venky Venkatesh (venky)]

 
Hi,
I am looking for any proc entry/tool which would provide the time for
which a thread/task has been sleeping. The use of this is the following:
I have a multi-threaded application and I am trying to determine the
extent of multi-processing between threads i.e. determine how much time
threads spend on blocking for resources/each other Vs doing productive
work. 
If the above is available, is there an additional info on
time-waiting-on-io (i.e. a subset of the above sleep time) that is also
available thru a proc entry/tool? This would find use in a server like
application where if all the current threads are spending most of their
time waiting on I/O then can add more threads.
In general if there is a proc entry which accounts for time spent by a
thread in various states that could also help.
	 
Thanx
-Venky

Re: Proc entry to know task/thread sleep time

[Andrew Morton]

On Wed, 22 Apr 2009 12:41:45 -0700 "Venky Venkatesh (venky)" <venky@cisco.com> wrote:

>  
> Hi,
> I am looking for any proc entry/tool which would provide the time for
> which a thread/task has been sleeping. The use of this is the following:
> I have a multi-threaded application and I am trying to determine the
> extent of multi-processing between threads i.e. determine how much time
> threads spend on blocking for resources/each other Vs doing productive
> work. 
> If the above is available, is there an additional info on
> time-waiting-on-io (i.e. a subset of the above sleep time) that is also
> available thru a proc entry/tool? This would find use in a server like
> application where if all the current threads are spending most of their
> time waiting on I/O then can add more threads.
> In general if there is a proc entry which accounts for time spent by a
> thread in various states that could also help.
> 	 

Do Documentation/accounting/delay-accounting.txt and
Documentation/accounting/getdelays.c suit?