On Tue, Jan 23, 2001 at 07:34:10PM -0000, eeh@netbsd.org wrote:

 > Here's a little fix I threw together to improve the performance of
 > UBC under I/O load.  What it does is put buffer cache pages on the
 > uvm inactive list when an IOP completes instead of leaving them on
 > the active list for the page scanner to reclaim.  This has several
 > effects:  it makes buffer cache pages more likely to be reclaimed
 > than other pages, and it slightly reduces the load on the pagedaemon.

This is a cool idea.  I'm refining it just a little.  In particular:

	- If the file is also mmap'd, you probably don't want to
	  deactivate the pages (and peanalize the process(es) that
	  have it mmap'd)

	- You probably only want to deactivate the pages that
	  were mapped in the UBC window, not all of the object's
	  pages.  This could be a big traversal for big objects :-)

I'll post a new patch in a bit.

-- 
        -- Jason R. Thorpe <thorpej@zembu.com>