Re: Use ZVC counters to establish exact size of dirtyable pages

[Christoph Lameter <clameter@sgi.com>]

On Wed, 14 Feb 2007, Christoph Lameter wrote:

> > This function will return zero.  Which I think we'll happen to handle OK.
> 
> One would expect the function to return 10. The 10 pages are on the LRU.
> If we really have zero dirtyable pages then we will get a division by 
> zero problem.

Well we do not have the division by zero problem due to this 
expression that really should also use available_memory

       unmapped_ratio = 100 - ((global_page_state(NR_FILE_MAPPED) +
                                global_page_state(NR_ANON_PAGES)) * 100) /
                                        vm_total_pages;

If we would change the basis here too (which is probably a good thing to 
do) then we may have the division by zero issue.

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>