[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-devel] Does blkback bypass Dom0's memory buffer?



On 04/02/14 22:15, xu cong wrote:
> Does blkback thread bypass Dom0's memory buffer? If I write in DomU
> without O_Direct, the data will be buffered in DomU's memory cache then
> be flushed to disk. Will them be buffered in Dom0's memory again? How
> about the netback? Thanks.

Blkback will not do any kind of buffering itself, the request is read
from the shared ring and passed to the underlying device using
submit_bio. If you want to make sure your data has hit the disk you
should issue a flush operation (see "feature-flush-cache" in blkif.h)

Roger.


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel


 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.