[OpenAFS-devel] enhance audit logs to support Sys V message queues

[Derrick Brashear]

>> You can choose to do non-blocking for named pipes. =A0 However, named
>> pipes (aka 'FIFO's to many in the Linux world) have a much tighter
>> coupling between producers and consumers than message queues do. =A0For
>> example, if a writer tries to write to a named pipe that =A0has no
>> readers, a SIGPIPE (or EPIPE if SIGPIPE is being ignored) is
>> generated
>
> Sometimes, I need to get more debugging info after the fact. I'm just
> wondering if queues function as a circular buffer when no readers are
> present. =A0I'm wondering how useful it would be to be able to get the la=
st X
> messages of maximum verbosity from a circular buffer. If something of
> interest happens, then ask the service to dump the circular buffer
> somewhere.
>
> Granted, this doesn't come up often, and I'm not sure how this would be
> better or worse than a memdump or something similar.

Auditlogs have limited value as a verbose events, since they represent
actions taken by clients, not things which were generated internally
by the fileserver event loops, for instance.

Derrick