[dm-devel] Multipath and LVM (lvdisplay takes 30Secs)

[ml ml]

Hello List,

i am using multipath for redundance reasons. But something seems to be dodgy.

"lvdisplay" takes 30Seconds.

"multipath" -l shows nothing

multipath -l -v 2
SAN (3600a0b80001f7557000032864ce4aff3) dm-0 IBM,1722-600
size=250G features='1 queue_if_no_path' hwhandler='1 rdac' wp=rw
|-+- policy='round-robin 0' prio=-1 status=active
| `- 2:0:1:0 sdb 8:16 active undef running
|-+- policy='round-robin 0' prio=-1 status=enabled
| `- 3:0:1:0 sdd 8:48 active undef running
`-+- policy='round-robin 0' prio=-1 status=enabled
  `- 3:0:0:0 sdc 8:32 active undef running

Any idea why lvmdisplay takes so long? If i can see its trying to read
from sda, dm-1, sdb, dm-1 where the "read(3, " operations need some
time each time.

Here is some more info:

multipath -l -v 3
May 15 12:10:06 | sdb: not found in pathvec
May 15 12:10:06 | sdb: mask = 0x1
May 15 12:10:06 | sdb: dev_t = 8:16
May 15 12:10:06 | sdb: size = 524288000
May 15 12:10:06 | sdb: subsystem = scsi
May 15 12:10:06 | sdb: vendor = IBM
May 15 12:10:06 | sdb: product = 1722-600
May 15 12:10:06 | sdb: rev = 0914
May 15 12:10:06 | sdb: h:b:t:l = 2:0:1:0
May 15 12:10:06 | sdb: tgt_node_name = 0x200400a0b816fb7
May 15 12:10:06 | sda: device node name blacklisted
May 15 12:10:06 | sdd: not found in pathvec
May 15 12:10:06 | sdd: mask = 0x1
May 15 12:10:06 | sdd: dev_t = 8:48
May 15 12:10:06 | sdd: size = 524288000
May 15 12:10:06 | sdd: subsystem = scsi
May 15 12:10:06 | sdd: vendor = IBM
May 15 12:10:06 | sdd: product = 1722-600
May 15 12:10:06 | sdd: rev = 0914
May 15 12:10:06 | sdd: h:b:t:l = 3:0:1:0
May 15 12:10:06 | sdd: tgt_node_name = 0x200400a0b816fb7
May 15 12:10:06 | sdc: not found in pathvec
May 15 12:10:06 | sdc: mask = 0x1
May 15 12:10:06 | sdc: dev_t = 8:32
May 15 12:10:06 | sdc: size = 524288000
May 15 12:10:06 | sdc: subsystem = scsi
May 15 12:10:06 | sdc: vendor = IBM
May 15 12:10:06 | sdc: product = 1722-600
May 15 12:10:06 | sdc: rev = 0914
May 15 12:10:06 | sdc: h:b:t:l = 3:0:0:0
May 15 12:10:06 | sdc: tgt_node_name = 0x200400a0b816fb7
May 15 12:10:06 | dm-0: device node name blacklisted
May 15 12:10:06 | dm-1: device node name blacklisted
May 15 12:10:06 | dm-2: device node name blacklisted
May 15 12:10:06 | dm-3: device node name blacklisted
May 15 12:10:06 | loop0: device node name blacklisted
May 15 12:10:06 | loop1: device node name blacklisted
May 15 12:10:06 | loop2: device node name blacklisted
May 15 12:10:06 | loop3: device node name blacklisted
May 15 12:10:06 | loop4: device node name blacklisted
May 15 12:10:06 | loop5: device node name blacklisted
May 15 12:10:06 | loop6: device node name blacklisted
May 15 12:10:06 | loop7: device node name blacklisted
May 15 12:10:06 | dm-4: device node name blacklisted
May 15 12:10:06 | dm-5: device node name blacklisted
May 15 12:10:06 | dm-6: device node name blacklisted
===== paths list =====
uuid hcil    dev dev_t pri dm_st chk_st vend/prod/rev dev_st
     2:0:1:0 sdb 8:16  -1  undef undef  IBM,1722-600  running
     3:0:1:0 sdd 8:48  -1  undef undef  IBM,1722-600  running
     3:0:0:0 sdc 8:32  -1  undef undef  IBM,1722-600  running
May 15 12:10:06 | params = 1 queue_if_no_path 1 rdac 3 1 round-robin 0
1 1 8:16 600 round-robin 0 1 1 8:48 600 round-robin 0 1 1 8:32 100
May 15 12:10:06 | status = 2 0 1 0 3 1 A 0 1 0 8:16 A 0 E 0 1 0 8:48 A
0 E 0 1 0 8:32 A 0
SAN (3600a0b80001f7557000032864ce4aff3) dm-0 IBM,1722-600
size=250G features='1 queue_if_no_path' hwhandler='1 rdac' wp=rw
|-+- policy='round-robin 0' prio=-1 status=active
| `- 2:0:1:0 sdb 8:16 active undef running
|-+- policy='round-robin 0' prio=-1 status=enabled
| `- 3:0:1:0 sdd 8:48 active undef running
`-+- policy='round-robin 0' prio=-1 status=enabled
  `- 3:0:0:0 sdc 8:32 active undef running

Any idea whats wrong here?

Thanks a lot,
Mario