Re: [Lse-tech] [RFC] [PATCH] Scalable Statistics Counters

[Ravikiran G Thirumalai <kiran@in.ibm.com>]

Hi Niels,
 
On Wed, Dec 05, 2001 at 10:02:33AM -0500, Niels Christiansen wrote:
>
> I'm wondering about the scope of this.  My Ethernet adapter with, maybe, 20
> counter fields would have 20 counters allocated for each of my 16
> processors.
> The only way to get the total would be to use statctr_read() to merge them.
> Same for the who knows how many IP counters etc., etc.
 
Are you concerned with increase in memory used per counter Here? I suppose
that must not be that much of an issue for a 16 processor box....
 
>
> How many and which counters were converted for the test you refer to?
>
 
Well, I wrote a simple kernel module which just increments a shared global
counter a million times per processor in parallel, and compared it with
the statctr which would be incremented a million times per processor in
parallel..
 
> I do like the idea of a uniform access mechanism, though.  It is well in
> line
> with my thoughts about an architected interface for topology and
> instrumentation
> so I'll definitely get back to you as I try to collect requirements.
>
> Niels
 
Hope we can come out with a really cool and acceptable interface..

Kiran
-- 
Ravikiran G Thirumalai <kiran@in.ibm.com>
Linux Technology Center, IBM Software Labs,
Bangalore.