task blocked for more than 120 seconds

[Josef 'Jeff' Sipek]

On Tue, Apr 24, 2012 at 09:27:59AM +1000, Dave Chinner wrote:
...
> So, yes, your hangs are definitely due to inode buffer RMW cycles
> when trying to flush dirty inodes from the cache. I have a few
> ideas on how to fix this - but I'm not sure whether a current TOT
> solution will be easily back-portable. The simplest solution is a
> readahead based solution - AIL pushing is async, and will cycle back
> to inodes that it failed to flush the first time past, so triggering
> readahead on the first pass might work just fine.

Have you had time to look at this?  (We got bitten by this again and I
really don't want to go back to ext4.)  Is there anything I can help with?

Jeff.

-- 
Evolution, n.:
  A hypothetical process whereby infinitely improbable events occur with
  alarming frequency, order arises from chaos, and no one is given credit.