Powerpath 5.2 and MPIO causing NPP leak

Ive seen a couple of cases now where Non paged pool memory is leaking and causing HTTP resourses to fail, machines to become unresponsive - the usual high NPP fun!

When looking at a poolmon of tags over time we see that the MPIO tag is leaking, this is the case with version 1.21 of MPIO when on a cluster. This is installed by default with PowerPath 5.2.

The current workaround is to downgrade to PowerPath 5.1 to fall back to a known good version of MPIO.sys

Unofficial word on the street is that PowerPath 5.2 SP1 may be available around mid December.

 

<Update>

5.2 SP1 of Powerpath is now available. So far it looks like we don't have the same issues with this build

 

<Update>

It looks like there may still be some issues around 5.2 SP1 (MPIO.sys v 1.22). So for the moment reverting back to something like 1.18 of MPIO.sys under the advice of the vendor would perhaps be a good idea... this is under investigation.