On Wed, Apr 30, 2014 at 7:24 PM, Darrick J. Wong
[off-list ref] wrote:

I haven't spent time on figuring out the other source of load average.  Kent
didn't seem to like the patch to convert the bcache_writeback thread to
interruptible sleep (I recall he said it was 'wrong', but didn't elaborate).

Sorry to hear that... Would be really nice to be able to go back to
normal load. And I cannot revert to an older kernel, as I need
3.15-rc2 or greater to fix a different problem concerning Oracle Java
:/