Re: Q: PAGE_CACHE_SIZE?

[Rik van Riel <riel@nl.linux.org>]

On Tue, 25 May 1999, Alan Cox wrote:

> > > Who's idea was it start the work to make the granularity of the page
> > > cache larger?
> > 
> > I guess the main motivation comes from the ARM port, where some versions
> > have PAGE_SIZE=32k.
> 
> For large amounts of memory on fast boxes you want a higher page
> size. Some vendors even pick page size based on memory size at
> boot up.

This sounds suspiciously like the 'larger-blocks-for-larger-FSes'
tactic other systems have been using to hide the bad scalability
of their algorithms.

A larger page size is no compensation for the lack of a decent
read-{ahead,back,anywhere} I/O clustering algorithm in the OS.
I believe we should take the more appropriate path and build
a proper 'smart' algorithm. Once we're optimizing for I/O
minimization, CPU is relatively cheap anyway...

Rik -- Open Source: you deserve to be in control of your data.
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