Re: Lockstats for SMP DB Workload

[Hanna Linder <hannal@us.ibm.com>]

--On Tuesday, June 04, 2002 17:16:46 -0700 Ruth Forester <lilo@us.ibm.com> wrote:

> Everyone, 
> 
> I am running with the following configuration
> 
> 	2.4.19pre8aa2+dj2+ (dj2 removes global semaphore_lock spinlock)
> 	 +fast_walkA3-2_4_19-pre8_patch.
> 
> The database is set up to use raw-io, yet looking at this data, it appears that
> I am still hitting a lot of filesystem accesses, among other things.  This is an
> oltp workload, although there are some contentions (pread?) that cause the 
> cpu sys time to go to 99%, it was during this part of the "workload" that this
> snapshot of lockmeter was taken.
> 

> SPINLOCKS         HOLD            WAIT
>   UTIL  CON    MEAN(  MAX )   MEAN(  MAX )(% CPU)     TOTAL NOWAIT SPIN RJECT  NAME
> 
>         6.7%  2.5us(  25ms)   62us(  12ms)( 6.8%)   2650959 93.3%  6.6% 0.05%  *TOTAL*
> 
>   2.4%  1.0%   38us(  15ms) 3185us(  12ms)(0.13%)      6291 99.0%  1.0%    0%  kernel_flag_cacheline
>   2.3%  9.1% 6865us(  15ms) 3551us(5592us)(0.01%)        33 90.9%  9.1%    0%    do_exit+0xf4


Dave Hanson has a do_exit patch you might want to look at...

Hanna