On Tue, 14 Feb 2012, Andrew Morton wrote:

On Tue, 14 Feb 2012 14:00:47 -0600 (CST)
Christoph Lameter [off-list ref] wrote:

quoted

On Tue, 14 Feb 2012, Mel Gorman wrote:

quoted

Thanks Stuart. Rik, Andrew, should the following be improved in some
way? I did not come to any decent conclusion on what to do with pages in
the inactive list with buffer_head as we are already stripping them when
the pages reach the end of the LRU.

We have made the statement in the past that configurations > 8GB on 32
bit should not be considered stable or supported? The fact is the more
memory you add on 32 bit the less low mem memory is available and the more
likely that an OOM will occur for any number of reasons.

I have memories of 16G being usable in earlier kernels.

16G regularly fell over in our environment so we now have an 8G max
restriction for those still using 32 bit.

Also, if an 8G machine works OK at present, it's only by luck.
sizeof(buffer_head) is around 100, so it takes 1.6GB of buffer_heads to
support 8G of 512-byte blocksize pagecache.

Well the slow kernel degradation in operation again. We also require
those 32 bit guys with the 8G limit to run older kernel versions...

--
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/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>