Re: [patch 00/14] Page cache cleanup in anticipation of Large Blocksize support

Andrew Morton
2007-06-14T20:07:20Z

On Thu, 14 Jun 2007 12:38:39 -0700
clameter@sgi.com wrote:

> This patchset cleans up the page cache handling by replacing
> open coded shifts and adds through inline function calls.

If we never inflict variable PAGE_CACHE_SIZE upon the kernel, these changes
become pointless obfuscation.

Let's put our horses ahead of our carts. We had a lengthy discussion about
variable PAGE_CACHE_SIZE in which I pointed out that the performance
benefits could be replicated in a manner which doesn't add complexity to
core VFS and which provides immediate benefit to all filesystems without
any need to alter them: populate contiguous pagecache pages with physically
contiguous pages.

I think the best way to proceed would be to investigate that _general_
optimisation and then, based upon the results of that work, decide whether
further _specialised_ changes such as variable PAGE_CACHE_SIZE are needed,
and if so, what they should be.