long hangs when deleting large directories (3.0-rc3)

[Markus Trippelsdorf]

On 2011.06.21 at 12:18 +0200, Markus Trippelsdorf wrote:
> On 2011.06.21 at 14:25 +1000, Dave Chinner wrote:
> > On Mon, Jun 20, 2011 at 01:13:59PM +0200, Markus Trippelsdorf wrote:
> > 
> > That is, you really need to get a profile of the rm -rf process - or
> > whatever is consuming the CPU time - (e.g. via perf or ftrace)
> > across the hang to so we can narrow down the potential cause of the
> > latency. Speaking of which, latencytop might be helpful in
> > identifying where input is getting held up....
> 
> Just ran latencytop and this the result:
> 
> [xlog_state_get_iclog_space]                      2104.4 msec         38.1 %

And another example:

Cause                                                Maximum     Percentage
[xlog_state_get_iclog_space]                      2098.7 msec         38.0 %
Waiting for TTY data                              1953.4 msec         29.7 %
Syncing filesystem                                 723.0 msec         12.1 %
Unlinking file                                      25.8 msec          7.7 %

-- 
Markus