Re: [PATCH 1/1] NBD: allow nbd to be used locally

[Pavel Machek]

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
-- 
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