On Friday 14 November 2008 20:00:23 Jens Axboe wrote: > Queue clustering is on by default though when you allocate your queue, > so I'm surprised you see a difference by doing: > > + /* Gather adjacent buffers to minimize sg length. */ > + queue_flag_set(QUEUE_FLAG_CLUSTER, vblk->disk->queue); > > did test_bit(QUEUE_FLAG_CLUSTER, &vblk->disk->queue->queue_flags) really > return 0 before? Apparently not. My results must be noise :( However, it made me look harder at the behaviour of the driver. I have two other enhancement patches while I'll send now, but I still only see sgs of 116 elements. Thanks for the clue donation, Rusty. _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/virtualization