Re: short term task list for Reiser4

[Hans Reiser <reiser@namesys.com>]

rvalles wrote:

>On Tue, Jul 11, 2006 at 03:04:20PM -0700, Hans Reiser wrote:
>  
>
>>Please feel free to comment on this list and the order of its tasks:
>>4) review complaints of pauses while using reiser4 --- size of task
>>unknown, and it is also unknown how much we may have fixed it while
>>writing recent patches.
>>
>>6) optimize fsync --- substantive task which requires using fixed area
>>for write twice logging, and using write twice logging for fsync'd
>>data.  It might require creating mount options to choose whether to
>>optimize for serialized sequential fsyncs vs. lazy fsyncs.
>>
>>    
>>
>I believe those two are related. I'm having the "pauses" (of many
>minutes at times!) when writing to reiser4. It seems it is triggered
>mostly by the use of fsync(); NFS in sync mode manages to trigger it
>way often: I mount my old desktop's home from my new computer via synced
>NFS.
>The pauses consist in the application being frozen and the other
>applications being slowed down on their IO operations, while the disks
>writes data continously during an interval that usually last a minute or
>so, but may last many times that. It often happens with small files
>(like, when sending a mail, as it passes through the MTA), so I believe
>it probably (re)writes to disk lots of stuff that doesn't need to be
>written to disk at all.
>It only happens on reiser4 patches against 2.6.13 or newer, 2.6.12.x is
>fine.
>  
>
So the pauses are experienced by a process waiting on fsync to finish?
If yes, then the problem is a very different issue from what I thought....

Hans