Heavy I/O requests makes the system unusable
|Reported by:||emitrax||Owned by:||nobody|
Couldn't find a better summary, sorry.
I was running 4 instances of bonnie++, plus a wget -r on a website, but that was on a different bfs partition.
The system became unusable quite soon. It looks like an infinite loop and not a deadlock, as there always was a thread ready (low resource manager and scsi scheduler).
To summarize: one instance of bonnie++ was waiting on a condition variable in steal_pages while holding the bfs journal lock. All the other three instances of bonnie++ were waiting for the journal lock. The page writer thread was also waiting on a condition variable on vfs_write_pages -> Request::Wait() .
Unfortunately I forgot to check the scsi scheduler thread backtrace.
I hope it helps.
I'm attaching the serial log.