Re: [PATCH RFC V10 0/18] Paravirtualized ticket spinlocks

[Andrew Jones <drjones@redhat.com>]

On Mon, Jun 24, 2013 at 06:10:14PM +0530, Raghavendra K T wrote:
> 
> Results:
> =======
> base = 3.10-rc2 kernel
> patched = base + this series
> 
> The test was on 32 core (model: Intel(R) Xeon(R) CPU X7560) HT disabled
> with 32 KVM guest vcpu 8GB RAM.

Have you ever tried to get results with HT enabled?

> 
> +-----------+-----------+-----------+------------+-----------+
>                ebizzy (records/sec) higher is better
> +-----------+-----------+-----------+------------+-----------+
>     base        stdev        patched    stdev        %improvement
> +-----------+-----------+-----------+------------+-----------+
> 1x  5574.9000   237.4997    5618.0000    94.0366     0.77311
> 2x  2741.5000   561.3090    3332.0000   102.4738    21.53930
> 3x  2146.2500   216.7718    2302.3333    76.3870     7.27237
> 4x  1663.0000   141.9235    1753.7500    83.5220     5.45701
> +-----------+-----------+-----------+------------+-----------+

This looks good. Are your ebizzy results consistent run to run
though?

> +-----------+-----------+-----------+------------+-----------+
>               dbench  (Throughput) higher is better
> +-----------+-----------+-----------+------------+-----------+
>     base        stdev        patched    stdev        %improvement
> +-----------+-----------+-----------+------------+-----------+
> 1x 14111.5600   754.4525   14645.9900   114.3087     3.78718
> 2x  2481.6270    71.2665    2667.1280    73.8193     7.47498
> 3x  1510.2483    31.8634    1503.8792    36.0777    -0.42173
> 4x  1029.4875    16.9166    1039.7069    43.8840     0.99267
> +-----------+-----------+-----------+------------+-----------+

Hmm, I wonder what 2.5x looks like. Also, the 3% improvement with
no overcommit is interesting. What's happening there? It makes
me wonder what < 1x looks like.

thanks,
drew