Hi,
On Tue, 08 Jun 1999 09:27:36 +1000, David Robinson <[EMAIL PROTECTED]>
said:
> I believe you could get into trouble if you start hitting swap (memory gets
> full).
> programs needs extra 1MB of ram...
> kernel doesn't have 1 MB of ram, kernel swaps something out to get 1MB ram.
> RAID drivers see the request to write to the swap partition and setup a 1MB
> buffer to dump the new data on the RAID.
> kernel recieves request for 1MB extra ram from RAID driver but doesn't have
> it.. kernel swaps something out to get 1MB.
Nope, it won't: we don't allow the recursive swap. On the recursive
call to try_to_free_pages, we are very careful only to throw away things
which can be done cheaply, without invoking IO and without stalling.
See the use of the PF_MEMALLOC flag in the mm/ subdir.
The 2.2 VM is much more robust against these sorts of potential
deadlocks than 2.0 was.
--Stephen
