Re: Subtle MM bug

[Zlatko Calusic <zlatko@iskon.hr>]

Rik van Riel <riel@conectiva.com.br> writes:

> Now if 2.4 has worse _performance_ than 2.2 due to one
> reason or another, that I'd like to hear about ;)
> 

Oh, well, it seems that I was wrong. :)


First test: hogmem 180 5 = allocate 180MB and dirty it 5 times (on a
192MB machine)

kernel | swap usage | speed
-------------------------------
2.2.17 |  48 MB     | 11.8 MB/s
-------------------------------
2.4.0  | 206 MB     | 11.1 MB/s
-------------------------------

So 2.2 is only marginally faster. Also it can be seen that 2.4 uses 4
times more swap space. If Linus says it's ok... :)


Second test: kernel compile make -j32 (empirically this puts the VM
under load, but not excessively!)

2.2.17 -> make -j32  392.49s user 47.87s system 168% cpu 4:21.13 total
2.4.0  -> make -j32  389.59s user 31.29s system 182% cpu 3:50.24 total

Now, is this great news or what, 2.4.0 is definitely faster.

-- 
Zlatko
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