Re: Yet another bogus piece of do_try_to_free_pages()

[Zlatko Calusic <zlatko@iskon.hr>]

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

> On 11 Jan 2001, Zlatko Calusic wrote:
> 
> > I have tested it for you and results are great. On some tests I got
> > 20% to 30% better results which is amazing. I'll do some more tests
> > but I would vote for this to get in immediately. Yes, it's *so* good.
> 
> Don't be so rash.
> 
> The patch hasn't been tested very thoroughly, otherwise
> people would have noticed the problem that PG_MEMALLOC
> isn't set around the page freeing code, possibly leading
> to deadlocks, triple faults and other nasties.
>

Oh, believe me I tested that patch very thoroughly with lots of
utilities, and it worked very very well. I don't remember that it
fiddled anywhere with the PG_MEMALLOC flag.

But, anyway, it's in the kernel now so I can delete
/boot/vmlinuz-marcelo which was my performance etalon, it was so
good. :)

> (and yes, I'm sure there will be somebody able to trigger
> this bug)
> 
> Remember that we - officially - still are in the 2.4 BUGFIX
> period, it's time to be careful with the code now and we should
> IMHO not randomly introduce new bugs in the name of performance.
>

Yeah, right! And Linus has just included reiserfs in a prepatch.

> Performance enhancements are perfectly fine, of course, but IMHO
> not after they've been posted 2 hours ago and haven't been
> reviewed and stresstested yet.
> 

They have been tested well enough.
-- 
Zlatko
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