Re: [Qemu-devel] [patch 2/5] qemu-nbd: merge NBD client/server

[Laurent Vivier <Laurent.Vivier@bull.net>]

Le jeudi 03 juillet 2008 à 09:21 +0200, Kevin Wolf a écrit :
> Thiemo Seufer schrieb:
> > Laurent.Vivier@bull.net wrote:
> >> This patch allows to connect directly a disk image file to an NBD
> >> device. It introduces the use of a unix socket (instead of inet).
> >>
> >> - To connect a file to a device:
> >>
> >> # qemu-nbd --connect=/dev/nbd0 my_disk.qcow2
> >>
> >> Then you can see directly your disk (no need of nbd-client):
> >>
> >> # fdisk -l /dev/nbd0
> >>
> >> Disk /dev/nbd0: 4294 MB, 4294967296 bytes
> >> 255 heads, 63 sectors/track, 522 cylinders
> >> Units = cylinders of 16065 * 512 = 8225280 bytes
> >>
> >>      Device Boot      Start         End      Blocks   Id  System
> >> /dev/nbd0p1   *           1         492     3951958+  83  Linux
> >> /dev/nbd0p2             493         522      240975    5  Extended
> >> /dev/nbd0p5             493         522      240943+  82  Linux swap /
> >> Solaris
> >>
> >> - To disconnect the file from the device:
> >>
> >> # qemu-nbd --disconnect /dev/nbd0
> >>
> >> Changelog:
> >> - v2: call show_parts() from client and avoid the sleep(1). Thank you to
> >> Avi and Anthony. Include my cleanup patch and comments from Carlo
> >> Marcelo Arenas Belon.
> >> - v3: allow to specify unix socket name with "--socket" and update 
> >> documentation.
> > 
> > There's still a call to sleep() in this patch.
> 
> And that's fine, IMHO. sleep() is not bad per se. The remaining call is
> not a "guess it'll take at most a second" style sleep but waiting in a
> loop until the child is ready. You don't want the loop to eat up 100%
> CPU, do you?

I agree.

Laurent
-- 
------------- Laurent.Vivier@bull.net ---------------
"The best way to predict the future is to invent it."
- Alan Kay