Re: VM: 2.4.10 vs. 2.4.10-ac2 and qsort()

From: Alan Cox (alan@lxorguk.ukuu.org.uk)
Date: Mon Oct 01 2001 - 14:42:27 EST


> I'm not sure either, since qsort doesn't really have much
> locality of reference but just walks all over the place.

qsort can be made to perform reasonably well providing you try to cache
colour the objects you sort and try to use prefetches a bit.

> I wonder how eg. merge sort would perform ...
 
Generally better but thats seperate to the VM issues.

> One thing which could make 2.4.10 faster for this single case
> is the fact that it doesn't keep any page aging info, so IO
> clustering won't be confused by the process accessing its
> pages ;)

I don't think that is too unusual a case. If the smarter vm is making poorer
I/O clustering decisions it wants investigating
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This archive was generated by hypermail 2b29 : Sun Oct 07 2001 - 21:00:16 EST