<div dir="ltr"><br><div class="gmail_extra"><br><div class="gmail_quote">On Thu, Nov 9, 2017 at 8:26 PM, Niels de Vos <span dir="ltr"><<a href="mailto:ndevos@redhat.com" target="_blank">ndevos@redhat.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><span class="gmail-">On Tue, Nov 07, 2017 at 05:59:32PM +0530, Pranith Kumar Karampuri wrote:<br>
> On Tue, Nov 7, 2017 at 5:16 PM, Niels de Vos <<a href="mailto:ndevos@redhat.com">ndevos@redhat.com</a>> wrote:<br>
><br>
> > On Tue, Nov 07, 2017 at 07:43:17AM +0530, Pranith Kumar Karampuri wrote:<br>
> > > hi,<br>
> > > I just created a github issue for reflink support<br>
> > > <<a href="https://github.com/gluster/glusterfs/issues/349" rel="noreferrer" target="_blank">https://github.com/gluster/<wbr>glusterfs/issues/349</a>>(#349) in glusterfs. We<br>
> > > are intending to use this feature to do block snapshots in gluster-block.<br>
> > ><br>
> > > Please let us know your comments on the github issue. I have added the<br>
> > > changes we may need for xlators I know a little bit about. Please help in<br>
> > > identifying gaps in implementing this FOP.<br>
> ><br>
> > For gluster-block it may be easier to have snapshot support in<br>
> > tcmu-runner instead? The qcow2 format would be ideal, and is in use by<br>
> > different Virtual Machine approaches running on Gluster already. There<br>
> > even is an upstream issue open for it:<br>
> > <a href="https://github.com/open-iscsi/tcmu-runner/issues/32" rel="noreferrer" target="_blank">https://github.com/open-iscsi/<wbr>tcmu-runner/issues/32</a><br>
> ><br>
> > Contributing towards this might be quicker than implementing file<br>
> > snapshot support in Gluster?<br>
> ><br>
><br>
> We tried that route by talking Fam Zheng, but the solution won't be<br>
> delivered in the timelines we are looking for.<br>
> So we went with this approach.<br>
<br>
</span>Ok, I am not sure if adding support for reflink in Gluster has an<br>
immediate benefit. It surely would be a great feature to have, but I do<br>
not know if it will land in enterprise kernels soon.<br></blockquote><div><br></div><div><a href="https://github.com/gluster/glusterfs/issues/377">https://github.com/gluster/glusterfs/issues/377</a> should address this concern until reflink becomes mainstream. <br></div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<br>
That said, I opened a GitHub issue to get reliable snapshot support in<br>
gluster-block. It describes an idea of the interface that could be<br>
implemented now already, without relying on reflink.<br>
<br>
<a href="https://github.com/gluster/gluster-block/issues/42" rel="noreferrer" target="_blank">https://github.com/gluster/<wbr>gluster-block/issues/42</a><br>
<br>
Obviously there is a need to sync/freeze data through tcmu-runner. This<br>
might require implementing a fsfreeze(8) like command in targetcli and<br>
tcmu-runner.<br>
<br>
Comments most welcome!<br>
<span class="gmail-HOEnZb"><font color="#888888">Niels<br>
</font></span></blockquote></div><br><br clear="all"><br>-- <br><div class="gmail_signature"><div dir="ltr">Pranith<br></div></div>
</div></div>