More likely, this is contention for the files_lock. Do you have any
lockmeter data ? That should give us more information. If so,
the files_struct_rcu isn't likely to help.
> 1168 find_get_page
> 1116 get_empty_filp
> Presumably that's the same thing? Interestingly, if I look back at
> previous results, I see it's about twice the cost in -mm as it is
> in mainline, not sure why ... at least against 2.5.37 virgin it was.
Not sure why it shows up more in -mm, but likely because -mm has
lot less contention on other locks like dcache_lock.
> > Please try running the files_struct_rcu patch where fget() is lockfree
> > and let me know what you see.
> Will do ... if you tell me where it is ;-)
Oh, the usual place -
I wish sourceforge FRS continued to allow direct links to patches.
-- Dipankar Sarma <email@example.com> http://lse.sourceforge.net Linux Technology Center, IBM Software Lab, Bangalore, India. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to firstname.lastname@example.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/