Re: [libvirt] [PATCH] Extra filesystem options during backend filesystem mount.

Daniel, Thanks for the pointers, i will keep this mind as and when the problem is fixed i will send a patch against those specific changes. Regards -- Harshavardhana Z Research Inc http://www.zresearch.com/ On Fri, Jul 17, 2009 at 11:58 PM, Daniel P. Berrange <berrange(a)redhat.com&gt;wrote: > On Thu, Jul 16, 2009 at 08:24:09PM +0530, Harshavardhana wrote: > > Hi Daniel, > > > > On Thu, Jul 16, 2009 at 7:46 PM, Daniel P. Berrange < > berrange(a)redhat.com&gt;wrote: > > > > > On Thu, Jul 16, 2009 at 06:06:25AM -0700, Harshavardhana wrote: > > > > New option index added to support -o options for various netfs. > > > > Currently added an option for glusterfs. > > > > > > What effect does it have ? Or why do we want/need it > > > > > > > Options could be required for filesystem to have few enhaced handling at > the > > site where they will be under use. Correct approach for a configurable > will > > be a new "XML" option in this case. > > > > Regarding current patch: > > This is required for the glusterfs to work properly with VM's. Right > now > > there is a > > problem/difficulty in using direct-io based mechanism in the fuse kernel > > module > > when used with "XEN" in its "tap:aio" framework, we have seen xen vms > hang > > over glusterfs or any fuse based filesystem due to fact that fuse module > > doesn't yet support "aio" with O_DIRECT internally as a kernel module. > To > > have a work around fix we have to hardcode this value due to its usage > in > > case of VM's. > > > > We are currently fixing this problem by fixing directly O_DIRECT problem > in > > fuse. Which will be available in later releases for kernel. > > ACK, I see why you need this for the current releases of kernel/glusterfs. > > As & when this problem is fixed we'll need to either remove this, or > provide a way to turn it off again. I don't think this is the kind of > tunable that should be exposed in the XML, since this is really just a > hack to work around a bug in a specific releases. Someone using libvirt > has no way to decide whether the hack is needed or not, so making them > set it in the XML would not be desirable. One possibility would be to > have a config file /etc/libvirt/storage.conf for controlling certain > options like this per host. > > Regards, > Daniel > -- > |: Red Hat, Engineering, London -o- > http://people.redhat.com/berrange/ :| > |: http://libvirt.org -o- http://virt-manager.org -o- > http://ovirt.org :| > |: http://autobuild.org -o- > http://search.cpan.org/~danberr/ <http://search.cpan.org/%7Edanberr/> :| > |: GnuPG: 7D3B9505 -o- F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 > :| > >