Re: Which is better at vm, and why? 2.2 or 2.4

[Mike Fedyk]

On Sat, Oct 13, 2001 at 01:48:05PM -0400, Mark Hahn wrote:
> > Now, the great kernel hacker, ac, said that 2.2 is better at vm in low
> > memory situations than 2.4 is. Why is this? Why hasnt someone fixed the 2.4
> > code? 
> 
> not to slight TGKH AC, but he's also the 2.2 maintainer; perhaps there's 
> some paternal protectiveness there ;)
> 
> my test for VM is to compile a kernel on my crappy old BP6 with mem=64m;
> I use a dedicated partition with a fresh ext2, unpack the same source tree,
> make -j2 7 times, drop 1 outlier, and average:
> 
> 2.2.19: 584.462user 57.492system 385.112elapsed 166.5%CPU
> 2.4.12: 582.318user 40.535system 337.093elapsed 184.5%CPU
>

Is this:
> 2.2.19: 
584.462user 
57.492system 
385.112elapsed 
166.5%CPU

> 2.4.12: 
582.318user 
40.535system 
337.093elapsed 
184.5%CPU

???

If so, then 2.4.12 won on user, system and elapsed.  What's with the CPU
percentage?  Are you on a dual system?

> notice that elapsed is noticably faster even than the 1+17 second
> benefit to user and system times.  Rik's VM seems to be slightly

No, that's Andrea's VM (since 2.4.10pre11).  Rik's is in 2.4.xx-ac.

Mike