On Thu, Jul 28, 2016 at 3:32 PM, Niels de Vos <ndevos@xxxxxxxxxx> wrote: > There are some features in QEMU that we could implement with the > existing libgfapi functions. Kevin asked me about this a while back, and > I have finally (sorry for the delay Kevin!) taken the time to look into > it. > > There are some optional operations that can be set in the BlockDriver > structure. The ones missing that we could have, or have useless > implementations are these: > > .bdrv_get_info/.bdrv_refresh_limits: > This seems to set values in a BlockDriverInfo and BlockLimits > structure that is used by QEMUs block layer. By setting the right > values, we can use glfs_discard() and glfs_zerofill() to reduce the > writing of 0-bytes that QEMU falls back on at the moment. Hey Niels and Kevin, In one of our discussions Jeff shown his interest in knowing about discard support in gluster upstream. I thinks his intention was same here. > > .bdrv_has_zero_init / qemu_gluster_has_zero_init: > Currently always returns 0. But if a file gets created on a Gluster > volume, it should never have old contents in it. Rewriting it with > 0-bytes looks unneeded to me. I agree > > With these improvements the gluster:// URL usage with QEMU (and now also > the new JSON QAPI), certain operations are expected to be a little > faster. Anyone starting to work on this would want to trace the actual > operations (on a single-brick volume) with ltrace/wireshark on the > system where QEMU runs. > > Who is interested to take this on? Of course I am very much interested to do this work :) But please expect at least a week or two at initializing this from my side, as currently my plate is filled with block store tasks. Hopefully this is meant for 2.8 (as 2.7 is in hard-freeze) I think delay should be acceptable. Thanks, -- Prasanna > Niels > > _______________________________________________ > Gluster-devel mailing list > Gluster-devel@xxxxxxxxxxx > http://www.gluster.org/mailman/listinfo/gluster-devel _______________________________________________ Gluster-devel mailing list Gluster-devel@xxxxxxxxxxx http://www.gluster.org/mailman/listinfo/gluster-devel
