Just the fact that you are using much bigger free queue sizes now means
that the batching in itself has less of an effect than with the smaller
queue sizes (here it's absolutely vital to get good merging).
> And the change to FIFO wakeup may have invalidated your earlier
> testing.
Could be, I'd inclined to think that FIFO behaviour would aid the
batching as well. Remember that we have had FIFO wakups there before, so
that's not entirely new.
> So hmm. I'll have a play with it, and if nothing obvious jumps
> out, I'll just clamp it at 32.
I think that would be best, I'll wait for numbers though :-). To be
honest, batch counts of eg 256 just sounds a bit insane to me.
-- Jens Axboe- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/