lkml.org 
[lkml]   [2002]   [Oct]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [linux-lvm] Re: [PATCH] 2.5 version of device mapper submission
Date
On Tuesday 15 October 2002 09:52, Kevin Corry wrote:
> Also, am I correct in assuming that for merge_bvec_fn() to work properly, a
> driver's merge_bvec_fn() must also call the merge_bvec_fn() of the driver
> below it? For example, lets say we have a DM linear device that maps to two
> underlying devices (or in LVM-speak, a linear LV that spans two PVs), both
> of which are MD RAID-1 devices. For a given large request, DM may decide
> that it is fully contained within one of its two target devices, and allow
> all the requested pages to be added to the bio. However, it also needs to
> ask MD what its limits are for that request, or MD would still have to go
> through the trouble to split up the bio after it has been submitted.

This example actually should have been RAID-0 (striping), not RAID-1
(mirroring). Sorry if this caused any confusion.

--
Kevin Corry
corryk@us.ibm.com
http://evms.sourceforge.net/
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:30    [W:0.036 / U:0.408 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site