RE: [lc-devel] Statistics: 0.21

[CIARROCCHI P. <Pao...@om...>]

> Just don't test intensively manual adaptivity using 0.22pre2, there a
> number of issues related to concurrency that I already fixed. A new
> 0.22pre3 will be available today or tomorrow.

Ok, I patched my kernel with 0.21, If I can this night I will perform
a test with this kernel and tomorrow I'll post the result.

> > Now, my questions:
> > + How many compressed cache I have to configure and how I can do it?
> 
> You can configure compressed cache initial size in kernel config
> options (in make config/menuconfig/xconfig). Another option is to use
> the kernel parameter in the boot time.
> 
> For example, starting the kernel image with compsize=4096 will boot
> the Linux kernel with a compressed cache of 16 MiB. 

Great, so I can compile the kernel with 128 Mib of compressed cache and
then force at the boot another value.
 
> Notice that the unit used to configure the compressed cache size is
> number of memory pages. Recall that a memory page in i386 is 4096
> bytes.

Ok, thanks.
 
> > + What kind of test can I run? Mmap001 300 should be ok?
> 
> You can test fillmem or mmap001 using a value at least near to fill
> all memory. If you have 256, a range of values from 200-350 would be
> nice to test. You can do it in steps of 10, 20, 30 MiB (it's up to
> you).

I'm gonna use the script I posted yesterday, then I think I'll modified it 
trying to have better report.

 
> It would also be great if you could test something closer to a normal
> workload. For example, loading the same set of programs and then
> measure the time taken to execute a program (eg. to load netscape
> browser). If you have some idea of a usual workload for you, it would
> be great to devise some sort of test to know how well the compressed
> cache could be helping this scenario.

Ok, I prefer test with "numerical" results, but I'll try to measure 
the time taken to execute program like netscape or GIMP.

> Oh, try to gather the compression statistics too (cat
> /proc/comp_cache_stat) after your tests. I forgot to do that when run
> the last tests.

Ok, I'll add it at my script.
 
> > If you could point me in the direction to look, I will perform a few
> > test using my laptop.
> 
> Thank you very much for the help!

My pleasure, 
the only problem if that I have few free time,
the work in Vodafone is very "eating time"... but with the laptop I
can perform the test while I coming back home :-)

Regards,
Paolo Ciarrocchi