<div dir="ltr">I was waiting to see your response to Ben's comment about the pref bit default values and tunable.</div><div class="gmail_extra"><br><div class="gmail_quote">On Fri, Jun 3, 2016 at 9:05 AM, Hannes Reinecke <span dir="ltr"><<a href="mailto:hare@suse.de" target="_blank">hare@suse.de</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><span class=""><br>
<br>
On 05/31/2016 10:34 PM, Sebastian Herbszt wrote:<br>
> Hannes Reinecke wrote:<br>
>> Recent kernels have an 'access_state' attribute which allows<br>
>> us to read the asymmetric access state directly from sysfs.<br>
>><br>
>> Signed-off-by: Hannes Reinecke <<a href="mailto:hare@suse.de">hare@suse.de</a>><br>
>> ---<br>
>> libmultipath/discovery.c | 33 +++++++++++++++++++++++++++++<br>
>> libmultipath/discovery.h | 2 ++<br>
>> libmultipath/prio.h | 1 +<br>
>> libmultipath/prioritizers/Makefile | 3 ++-<br>
>> libmultipath/prioritizers/sysfs.c | 43 ++++++++++++++++++++++++++++++++++++++<br>
>> libmultipath/propsel.c | 6 +++++-<br>
>> multipath/multipath.conf.5 | 14 ++++++++++++-<br>
>> 7 files changed, 99 insertions(+), 3 deletions(-)<br>
>> create mode 100644 libmultipath/prioritizers/sysfs.c<br>
><br>
> How about just adding this to the alua prioritizer?<br>
> This new feature could then depend on a "sysfs" argument.<br>
><br>
</span>No. The 'sysfs' prioritizer is using the abstract kernel sysfs<br>
interface, for which every device handler provides the information.<br>
So in theory it's independent on the underlying device handler.<br>
<br>
However, only the ALUA device handler has been reworked to provide<br>
up-to-date information; for the other device handlers there is a<br>
risk of the sysfs information is getting out-of-date.<br>
<br>
Hence I've restricted the 'detect_prioritizer' algorithm to select<br>
'sysfs' only if an ALUA system is present.<br>
But this doesn't imply in any way that the 'sysfs' prioritizer can be<br>
used only for ALUA systems.<br>
<br>
Christophe, what about merging the patch?<br>
<br>
Cheers,<br>
<br>
Hannes<br>
</blockquote></div><br></div>