Re: [Nbd] [PATCH 1/1] NBD: allow nbd to be used locally
On Mon 2008-03-10 13:26:34, Paul Clements wrote:
> Pavel Machek wrote:
>
>>> This patch allows a Network Block Device to be mounted locally
>>> (nbd-client to nbd-server over 127.0.0.1).
>>>
>>> It creates a kthread to avoid the deadlock described in NBD tools
>>> documentation. So, if nbd-client hangs waiting for pages, the kblockd
>>> thread can continue its work and free pages.
>>
>> What happens if your new kthread blocks on memory allocation?
>
> Well, we expect that. The reason for the new thread is so that it hangs,
> rather than kblockd hanging (which on a UP system brings all I/O to a
> halt). As long as kblockd can continue making progress, we eventually free
> up memory and then NBD can finish its requests, too.
...unless all the memory is in dirty buffers for nbd, and nbd server
is swapped out or something?
Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
Reply to: