Hello there, i just came with some benchmarks:
Done on p166-24M
No flames please - i know these were low VM loads, i did this just to know
how big is test rmaps maitenance overhead. It shows us that even on low VM
load there is a huge win in using rmap. And the win increases with the VM load.
Algo:
- booted ac12
- performed test A 7 times, then test B 7 times.
- booted ac12-pmap2
- performed test A 7 times, then test B 7 times.
* each test was done 7 times, with the lowest and highest thrown away.
* due to high values of data and streaming usage pattern caching was
unable to affect results, so it was ignored.
test A:
"time find / -xdev" + (standard junk eating ~6% cpu (top procinfo))
descr: extremely low VM load, mostly IO dependent
test B:
"time find / -xdev | grep --regexp="\/" | xargs echo" + background mpg123 +
+ standard junk described above
descr: low, although higher than A, vm load (nearly absolutely no swap)
Results:
ac12 ac12-pmap2
===[ test A: find / -xdev
real 1m4.221s 0m56.916s
real 1m3.042s 0m57.275s
real 1m3.613s 0m57.606s
real 1m3.442s 0m57.166s
real 1m3.447s 0m56.895s
======================================
avg 63.553 sec 57.171 sec 11% win
sys 0m36.750s 0m31.980s
sys 0m37.190s 0m31.870s
sys 0m36.720s 0m32.300s
sys 0m36.650s 0m32.400s
sys 0m37.350s 0m32.270s
======================================
avg 36.93 sec 32.16 sec 13% win
===[ test B: find / -xdev | grep --regexp="\/" | xargs echo (with mpg123 in bgrnd
eating 4M+ buf + 15-20% CPU)
real 0m38.720s 0m31.018s
real 0m38.061s 0m30.318s
real 0m38.075s 0m31.980s
real 0m37.626s 0m31.149s
real 0m38.431s 0m30.820s
======================================
avg 38.182 sec 31.057 sec 19% win
sys 0m16.090s 0m13.910s
sys 0m15.820s 0m13.610s
sys 0m15.750s 0m13.710s
sys 0m15.700s 0m13.780s
sys 0m15.750s 0m13.790s
======================================
avg 15.82 sec 13.76 sec 14% win
cheers,
Sam
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Fri Sep 07 2001 - 21:00:14 EST