[Pvfs2-developers] threaded client-core and the device thread

[Sam Lang]

I'm working with your branch Walt.  Most of the code that does  
allocation of the client state machines is the same.

-sam

On Oct 24, 2006, at 9:10 AM, Walter B. Ligon III wrote:

> Should be careful here, since all of the code dealing with  
> PINT_client_sm's have been rewritten for the new SM code and  
> Murali's suggestions (for example) may not work so well.
>
> Walt
>
> Murali Vilayannur wrote:
>> Hey Sam,
>>> I ran pvfs2-client-core in valgrind, and then ran Bonnie++ a few  
>>> times (10) on the mounted pvfs volume, and noticed the following  
>>> when I stopped the client process:
>>>
>>> ==20132== malloc/free: 1,298,824 allocs, 1,297,888 frees,  
>>> 3,462,517,583 bytes allocated.
>>>
>>> Allocating and freeing 3.5GB seemed extreme, so I went  
>>> exploring.  It turns out that every time we allocate a  
>>> PINT_client_sm, we're allocating about 35KB:
>>>
>>> (gdb) p sizeof(struct PINT_client_sm)
>>> $4 = 37764
>> Oh boy.. that is definitely large..
>>>   static array of 8 PINT_client_lookup_sm_ctx, which itself has a  
>>> static array 40 PINT_client_lookup_sm_segment, which are each  
>>> about 112 bytes.  Anyway, it ends up accumulating.
>>>
>>> So I'm convinced at this point that this is beyond the noise  
>>> range, plus its just cruft that we don't need.  I'd like to swap  
>>> out those static arrays for dynamic allocation when we get to the  
>>> start of the lookup state machine.  Any thoughts or suggestions?
>> I agree. It definitely does not look like noise region anymore.
>> How about we keep a pool of PINT_client_sm's around in client-core  
>> and allocate from that instead of dynamically allocating one  
>> everytime?
>> My 2 cents :)
>> thanks,
>> Murali
>> _______________________________________________
>> Pvfs2-developers mailing list
>> Pvfs2-developers at beowulf-underground.org
>> http://www.beowulf-underground.org/mailman/listinfo/pvfs2-developers
>
> -- 
> Dr. Walter B. Ligon III
> Associate Professor
> ECE Department
> Clemson University
>