Messages in this thread | | | Date | Tue, 26 Feb 2013 11:30:30 +0200 | From | "Michael S. Tsirkin" <> | Subject | Re: [PATCH 02/16] virtio_ring: virtqueue_add_sgs, to add multiple sgs. |
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On Tue, Feb 26, 2013 at 03:44:26PM +1030, Rusty Russell wrote: > "Michael S. Tsirkin" <mst@redhat.com> writes: > > On Tue, Feb 19, 2013 at 06:26:20PM +1030, Rusty Russell wrote: > >> virtio_scsi can really use this, to avoid the current hack of copying > >> the whole sg array. Some other things get slightly neater, too. > >> > >> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> > > > > Hmm, this makes add_buf a bit slower. virtio_test results > > (I'll send a patch to update the test shortly): > > > > Before: > > 0.09user 0.01system 0:00.12elapsed 91%CPU (0avgtext+0avgdata 480maxresident)k > > 0inputs+0outputs (0major+145minor)pagefaults 0swaps > > > > After: > > 0.11user 0.01system 0:00.13elapsed 90%CPU (0avgtext+0avgdata 480maxresident)k > > 0inputs+0outputs (0major+145minor)pagefaults 0swaps > > Interesting: how much of this is due to the shim in virtqueue_add_buf() > to clean up the sg arrays? > > (Perhaps we should make virtio_test run for longer, too). > > BTW, you might be interested in: > https://github.com/rustyrussell/stats.git > > Which provides a useful filter for multiple results. > > Cheers, > Rusty.
Nifty.
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