Re: hibernate takes long time with huge file transfers

[Robert Hancock <hancockrwd@gmail.com>]

On 09/11/2009 12:04 PM, Anil kumar wrote:
> Hi,
>
> I am running a huge file transfer by using simple dd command. I see that the process state of this dd is "D" uninterruptible sleep. Now I hibernate the system.
>
> what I observe is that hibernate takes long time to complete. Looks like its waiting for the "dd" command to complete.
> My understanding is that since the process is in uninterruptible sleep, hibernate is not able to stop the task.
>
> Question:
> 1. Does hibernation work this way wherein it waits for the process to complete and then hibernate. Especially if the process is in uninterruptible sleep state.
> 2. What if the process is not in uninterruptible sleep?

I don't imagine the fact it's in D state would have anything to do with 
it, more likely that it's constantly generating writes and the 
hibernation process does a sync, which may take a long time if something 
is dirtying memory as fast it can be written out..

> 3. Does sync'ing also adds to longer durations?
>
> Thanks in advance for the help.
>
> With regards,
>     Anil
>
>
>