[dm-devel] multipath-tools and queue-length/service-time path selectors oops

[Kiyoshi Ueda]

Hi Andy,

Sorry for the late reply.

On 09/15/2009 11:35 PM +0900, Andy wrote:
> Now, I have another question. Why does the queue-length selector not use all
> my paths?
> 
> Sep 15 09:25:44 | loop0: device node name blacklisted
> Sep 15 09:25:44 | loop1: device node name blacklisted
<snip>
> Sep 15 09:25:44 | params = 0 0 1 1 queue-length 0 4 1 8:64 8 8:144 8 8:224 8 65:48 8 
> Sep 15 09:25:44 | status = 2 0 0 0 1 1 A 0 4 1 8:64 A 0 0 8:144 A 0 0 8:224 A 0 0 65:48 A 0 0 
> Sep 15 09:25:44 | 8: not found in pathvec
> Sep 15 09:25:44 | Invalid device number 8
> Sep 15 09:25:44 | Invalid device number 8
<snip>
> reload: u02 (350002ac000020246) undef 3PARdata,VV
> size=100G features='0' hwhandler='0' wp=undef
> `-+- policy='queue-length 0' prio=4 status=undef
>   |- 1:0:0:3 sde 8:64  active ready running
>   |- 1:0:1:3 sdj 8:144 active ready running
>   |- 2:0:0:3 sdo 8:224 undef ready running
>   `- 2:0:1:3 sdt 65:48 undef ready running
> Sep 15 09:25:49 | Invalid device number 8
> Sep 15 09:25:49 | Invalid device number 8
> 
> 
> u02 (350002ac000020246) dm-3 3PARdata,VV
> size=100G features='0' hwhandler='0' wp=rw
> `-+- policy='queue-length 0' prio=2 status=active
>   |- 1:0:0:3 sde 8:64  active ready running
>   |- #:#:#:# -   #:#   active faulty running
>   |- 1:0:1:3 sdj 8:144 active ready running
>   `- #:#:#:# -   #:#   active faulty running

Actual device configuration seems to be working fine, but the getting
information from the configured device seems to be failing due to
table parsing problem in disassemble_map().
(The RHEL5's device-mapper-multipath package works fine.
 So the problem seems to be introduced during upstream development.)

I guess the attached patch works around the problem. Please try it.
Please note that this patch may *NOT* be a complete fix.
Some more codes for new dynamic load balancers may be needed.

By the way, unfortunatelly, I can't work on this next week.
I'll look at this more after that.  Sorry for the inconvenience.

Thanks,
Kiyoshi Ueda

---
 libmultipath/dmparser.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

Index: multipath-tools/libmultipath/dmparser.c
===================================================================
--- multipath-tools.orig/libmultipath/dmparser.c
+++ multipath-tools/libmultipath/dmparser.c
@@ -323,8 +323,10 @@ disassemble_map (vector pathvec, char * 
 							def_minio /= pp->priority;
 
 						FREE(word);
-					} else
+					} else {
+						p += get_word(p, NULL);
 						def_minio = 0;
+					}
 
 					if (def_minio != mpp->minio)
 						mpp->minio = def_minio;