mbuf leakage with nfs/udp (was mbuf leakage with nfs/zfs?)

[Daniel Braniss]

> 
> 
> On Wed, 3 Mar 2010, Daniel Braniss wrote:
> 
> > disabling the krpc reply cache does it, no visible damage. Somehow
> > this reminds me of my old 1970 beetle, parts would fall off but it would
> > continue working :-)
> > where to go from here?
> >
> Ok, so it sounds like the leak is in the krpc reply cache code, if I
> understand this? (ie. you are running the regular server with the reply
> cache disabled and the UDP client mounts aren't causing the leak.)

correct. The interesting side effect, is that I can't see any negative
issues when disabling the cash.
> 
> Good work on tracking this down!
> 
it was a coordinated efford :-)

> I guess the next step is to look through the code for the leak. I'll
> do that someday, but if anyone else is inspired to do so, they are
> more than welcome.:-)
> 
> Thanks for working through this, rick

thank you! I have a vested interest in having this fixed, on the other hand 
nfsd
seems ok, I have been running it now on a semi production server and
it's holding up quiet nicely, the cache seems not up to expectations:

store-mg-03# nfsstat -se
Server Info:
  Getattr   Setattr    Lookup  Readlink      Read     Write    Create    Remove
 48176764    262687  12582599     19732   4225907   9186574    780793    818837
   Rename      Link   Symlink     Mkdir     Rmdir   Readdir  RdirPlus    Access
     7623       160     27753     59551     59552    118216         0   1992779
    Mknod    Fsstat    Fsinfo  PathConf    Commit   LookupP   SetClId SetClIdCf
        0    979005        19         0   1644267         0         0         0
     Open  OpenAttr OpenDwnGr  OpenCfrm DelePurge   DeleRet     GetFH      Lock
        0         0         0         0         0         0         0         0
    LockT     LockU     Close    Verify   NVerify     PutFH  PutPubFH PutRootFH
        0         0         0         0         0         0         0         0
    Renew RestoreFH    SaveFH   Secinfo RelLckOwn  V4Create
        0         0         0         0         0         0
Server:
Retfailed    Faults   Clients
        0         0         0
OpenOwner     Opens LockOwner     Locks    Delegs 
        0         0         0         0         0 
Server Cache Stats:
   Inprog      Idem  Non-idem    Misses CacheSize   TCPPeak
      307         0       297  80943198         0         0

danny