[dm-devel] dm-log-userspace: Allow mark requests to piggyback on flush requests

[Mike Snitzer]

On Mon, Jan 13 2014 at  9:30pm -0500,
Jonathan Brassow <jbrassow at redhat.com> wrote:

> dm-log-userspace: Allow mark requests to piggyback on flush requests
> 
> In the cluster evironment, cluster write has poor performance.
> Because userspace_flush has to contact userspace program(cmirrord)
> in clear/mark/flush request. But both mark and flush requests
> require cmirrord to circle message to all the cluster nodes in each
> flush call.  This behave is realy slow. So the idea is merging
> mark and flush request together to reduce the kernel-userspace-kernel
> time.  Allow a new directive, "integrated_flush" that can be used to
> instruct the kernel log code to combine flush and mark requests when
> directed by userspace.  Additionlly, flush requests are performed
> lazily when only clear requests exist.
> 
> Signed-off-by: dongmao zhang <dmzhang at suse.com>
> Signed-off-by: Jonathan Brassow <jbrassow at redhat.com>

Hey Jon,

Thanks for following through with this.  Should it be attributed to
dongmao as the author?