What are the advantage of maintaining the Power Path

AFAIK, the mainteance on Power Path is only the "version upgrade" periodically to keep up with the EOSL or to fight with the effected bugs. PP upgrade(requires reboot) we normally propose with other system related acitivities to avoid a separate outages. But I have noticed that not much people really cares about the EOSL or the bugs and we are still have systems with PP versions 3.0.3 on critical production servers.

Do micro code upgrade of SYM or flare code upgrade on CLAR recommends to keep the Sulution Enabler and PP (which ever applicable) updated. I am thinking why the PP left unupgraded even though the codes on array are updated.

Can i say PP is an integral part of the SAN ?Maintaining PP and array should get imprtance and should be under same umberla; is it??


I am concerned about PP as we have seen many possible bugs pointing to PP with old versions which effect systems availability. Here is one case(with version 4.5) where multiple threads that are hung in a set of EMC Powerpath code routines while trying to do I/Os.

Here is how stack trace looks like

proc_list{47} pid=77 tid=131 cmd="MpcPeriodicCallbackDaemon"
p_stat="SINUSE" : kt_stat="TSSLEEP"
Process : p proc_t 0x103d6a040
pid=77 MpcPeriodicCal
Kthread : p kthread_t 0x103d6b040
Using PCB: p user_t 0xff37400.0x400003ffffff0000
SR5=0xff37400
LVL FUNC ARG0 ARG1 ARG2 ARG3 ARG4 ARG5 ARG6 ARG7
0) _sleep+0x380 0x103d39390 0x294 n/a n/a n/a n/a n/a n/a
1) PowerSleep+0x6c 0x103d39390 0x103d39358 n/a n/a n/a n/a n/a n/a
2) PowerGetSema+0x1c0 0x103d39358 n/a n/a n/a n/a n/a n/a n/a
3) PowerServiceDaemonQ+0x34 0x103d39300 n/a n/a n/a n/a n/a n/a n/a
4) PowerPlatformCreateDaemonProc+0xac n/a n/a n/a n/a n/a n/a n/a n/a
5) PowerServiceDaemonQ+0xe8 0xebb10400 n/a n/a n/a n/a n/a n/a n/a
6) PowerPlatformCreateDaemonProc+0xac n/a n/a n/a n/a n/a n/a n/a n/a
7) PiocDaemon+0x118 0x40004000 0x262a5837 n/a n/a n/a n/a n/a n/a
8) power_pseudo_ioctl+0xcc n/a 0xffffffff80105060 0x103cea040 0x3 n/a n/a n/a n/a
9) spec_ioctl+0xac 0x103cab048 0xffffffff80105060 0x103cea040 0x3 n/a n/a n/a n/a
10) vno_ioctl+0x98 0x86a2faf8 0xffffffff80105060 0x103cea040 n/a n/a n/a n/a 0xb8900d0
11) ioctl+0x118 0x400003ffffff03a0 n/a n/a n/a n/a n/a n/a 0x8a2464c
12) syscall+0x204 n/a n/a n/a n/a n/a n/a n/a n/a
13) syscallinit+0x55c n/a n/a n/a n/a n/a n/a n/a n/a

Other way of saying alot of Powerpath related I/Os that seem to be stuck

LVL FUNC

0) _sleep+0x380

1) PowerSleep+0x6c

2) PowerGetSema+0x1c0

3) PowerServiceDaemonQ+0x34

4) PowerPlatformCreateDaemonProc+0xac

5) PowerServiceDaemonQ+0xe8

6) PowerPlatformCreateDaemonProc+0xac

7) PiocDaemon+0x118

8) power_pseudo_ioctl+0xcc

9) spec_ioctl+0xac

10) vno_ioctl+0x98

11) ioctl+0x118

12) syscall+0x204

13) syscallinit+0x55c


I am curious who make sure(owns) that PP versions are updated on your shops???Why or why NOT maintaning PP should be an integral part of keeping a SAN healthy?