Dear Managers,
I am posting again about a problem that has occurred with a number of
our Alpha systems.
The problem has occured on a number of our machines, but generally is
confined to our main server. Periodically (about once per week) the machine
refuses any NFS requests. Although the server itself is fine all other
machines report "NFS3 server fubar not responding still trying".
The most common response was to upgrade to 3.2C, which I shall do soon,
but at the moment the problems persist and I would be grateful if
anyone could shed further light on the subject.
If I do a vmstat -M when the alpha fails to serve via NFS I see a lot of
memory allocated to VNODE, MBUF and MCLUSTER. For example
MBUF = 193536 MCLUSTER = 360448 SOCKET = 61440
PCB = 79744 ROUTETBL = 1568 IFADDR = 1152
MBLK = 15616 MBLKDATA = 32448 STRHEAD = 13824
STRQUEUE = 37376 STRMODSW = 2432 STRSYNCQ = 9664
STREAMS = 4432 FILE = 25152 DEVBUF = 35072
UFS MOUNT = 3072 IPM ADDR = 128 IFM ADDR = 192
VNODE = 6460416 DMASG = 9184 KALLOC = 1597408
TEMP = 192
compared to the newly booted system
MBUF = 15104 MCLUSTER = 2048 SOCKET = 29440
PCB = 39424 ROUTETBL = 1568 IFADDR = 1152
MBLK = 3584 MBLKDATA = 3136 STRHEAD = 6144
STRQUEUE = 13824 STRMODSW = 2432 STRSYNCQ = 3776
STREAMS = 3472 FILE = 12992 DEVBUF = 23040
UFS MOUNT = 3072 IPM ADDR = 128 IFM ADDR = 192
VNODE = 1017856 IO BUF = 256 DMASG = 9184
KALLOC = 1481120 TEMP = 192
Previous responses have suggested that a Sun client can cause a memory
leak seen as an increase in MBUFs. I do have a single Sun NFS client,
but it does not get used much and MBUFs do not increase steadily, rather
there is a sudden increase around the failure time. Can someone enlighten
me as to what MBUFs and MCLUSTERS actually are and what I might be seeing ?
Thanks,
Paul
+ Paul Collison p.collison1_at_physics.oxford.ac.uk +
| Starlink Computer Systems Manager |
| Astrophysics, Nuclear and Astrophysics Lab., tel: +44 1865 273311 |
+ Keble Road, Oxford, OX1 3RH, ENGLAND. fax: +44 1865 273390 +
Received on Tue Dec 12 1995 - 20:19:41 NZDT