Vimage globals vs structures measurements.

[Julian Elischer]

Julian Elischer wrote:
> 
> anyone who has commands and args for their favourite
> thing the'd like me to test... send it in..
> 
> 
> so far using ttcp I have seem no measureable difference.
> 
> but I have more tests to do of course..
> 
> for example throughput with small packets with ttcp (KB/Sec)....
> 
> 
> x VIMAGE_GLOBALS
> + NO_VIMAGE_GLOBALS
> +-----------------------------------------------------------------+
> |                                         +   xx                  |
> |                                         +   xxx           +     |
> |                                         +   xxx   x      ++++   |
> |               x        +       x      + +   xxxxxxx      +++++  |
> |x    +  ++ xx xxx  +  ++++xxx x x x   +++++ ***xxxxx     ++++++++|
> |                        |_____________A______M______|            |
> |                           |________________AM________________|  |
> +-----------------------------------------------------------------+
>     N           Min       Max      Median         Avg      Stddev
> x  40      48016.01   57361.32    56268.06   54915.582   2554.0133
> +  40      48999.66   59646.59    56261.58   56086.798   3119.1782
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as I said before  mst of my tests have shown no real change but this 
one has the most change I've seen.. it's 160 byte udp packets sent 
between two identical machines (both using the same kernel each time).


x VIMAGE_GLOBALS
+ NO_VIMAGE_GLOBALS
+-----------------------------------------------------------------+
|                     +   +     ++   xx x x                       |
|                   + +  ++   +x++x +xx x x                       |
|                   + + +++ + +*+**x+xxxx x                       |
|                 + +++ +++x*++*+**x*x*xx x x       x             |
|                 + +*+++++x**+*+**x*x*x*xx x x     xx            |
|                ++++*++++****+*+**x*x****x xxxx   xxx            |
|    + +   xx +  ++++*++*+****+***********x*xxxxx xxxx           x|
|+   +*+++ xx++*+*+*+****+****************x***x*xxx*xx   x  xx   x|
|                         |__________A__________|                 |
|                 |_________A________|                            |
+-----------------------------------------------------------------+
     N           Min       Max    Median        Avg        Stddev
x 150      10175.11  11292.11  10763.80    10760.77    200.92124
+ 150      10075.64  11019.12  10591.68    10580.059   172.29227
Difference at 95.0% confidence
         -180.711 +/- 42.3572
         -1.67935% +/- 0.393626%
         (Student's t, pooled s = 187.155)

this one showed a 1.7% slowdown
where the one above showed a half percent speedup
(but not considered significant).

The first one shown above was TCP with 1500 byte packets on bge 1G 
interfaces..

more test ideas appreciated...