Re: [PATCH 02/10] mm: system wide ALLOC_NO_WATERMARK

On Monday 06 August 2007 11:51, Christoph Lameter wrote:
On Mon, 6 Aug 2007, Daniel Phillips wrote:
On Monday 06 August 2007 11:42, Christoph Lameter wrote:
On Mon, 6 Aug 2007, Daniel Phillips wrote:
Currently your system likely would have died here, so ending up
with a reserve page temporarily on the wrong node is already an
improvement.

The system would have died? Why?

Because a block device may have deadlocked here, leaving the system
unable to clean dirty memory, or unable to load executables over
the network for example.

So this is a locking problem that has not been taken care of?

A deadlock problem that we used to call memory recursion deadlock, aka:
somebody in the vm writeout path needs to allocate memory, but there is
no memory, so vm writeout stops forever.

Regards,

Daniel
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