server hangs at random times approximately once a day with RPC: sendmsg
returned error 12. Requires hard reset.
We're running kernel-2.4.21-47.EL on AS 3 update 3. We set /proc/sys/vm/vm-
defragment to 100 but it did not alleviate the problem.
This server is an email server that is an NFS client.
Opening new ticket at request of Larry Woodman. There is a related closed bug
report # 123226.
An interesting side note:
I tried out two new "defrag" kernels from Larry. In both cases, enabling sysrq
and the server immediately proceeds to go from its normal operating load of 4
to 150. At one point yesterday the load reached 450 before we disabled sysrq
I'd like to be able to get sysrq -m data to post but can't do it until the load
issue is fixed.
Another thing I'd like to note: in the previous bug report, there seemed to be
a trend of using Proliant servers among the users reporting the problem. We're
using one too, so perhaps a Proliant / Xeon / Intel issue here?
Created attachment 138691 [details]
sysrq output during rcp errors
Created attachment 139147 [details]
kernel 2.4.21-40.ELsmp sysrq memdump
sysrq -m output during rpc 12 errors, running kernel 2.4.21-40.ELsmp.
We've got other sysrq output, not just mem, from this crash, if you need it.
Michael, what are the NFS mount options? Specifically I'm looking for the MTU
size that RPC is using, that is the underlying cause of the memory allocation
failure. The kernel/VM can only try to deal with defragmenting memory once it
has become highly fragmented.
This bug is filed against RHEL 3, which is in maintenance phase.
During the maintenance phase, only security errata and select mission
critical bug fixes will be released for enterprise products. Since
this bug does not meet that criteria, it is now being closed.
For more information of the RHEL errata support policy, please visit:
If you feel this bug is indeed mission critical, please contact your
support representative. You may be asked to provide detailed
information on how this bug is affecting you.