On Wed, May 27, 2015 at 5:36 PM, Alasdair G Kergon <a...@redhat.com> wrote: > On Wed, May 27, 2015 at 04:42:44PM -0700, Ming Lin wrote: >> Here are fio results of XFS on a DM stripped target with 2 SSDs + 1 HDD. >> Does it make sense? > > To stripe across devices with different characteristics? > > Some suggestions. > > Prepare 3 kernels. > O - Old kernel. > M - Old kernel with merge_bvec_fn disabled.
How to disable it? Maybe just hack it as below? void blk_queue_merge_bvec(struct request_queue *q, merge_bvec_fn *mbfn) { //q->merge_bvec_fn = mbfn; } > N - New kernel. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/