kernelNFS(lockd) problem and patch suggestion

[Juan Gomez]

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Hi all,

I noticed that after starting a linux NFS server, the first lock request
gets delayed about 30 seconds even after waiting the 45 seconds
corresponding to the grace period.
At first I thought this was due to the fact that being the first time a
lock is acquired through the server lockd/statd interaction was required
and the creation of a new file was involved
(i.e. statd/sm/client_IP) but still 30 seconds was way too long...

After taking a look at the code I realized that the lockd thread sets grace
period and then goes to sleep for a long time waiting for messages and the
first message always gets processed
before checking if the grace period has completed (which it might after
sleeping for a long time).

I think this can be easily fixed by clearing the grace period after waiting
for messages and before procesing them for correct operation as described
in the following patch.

I will appreciate if this patch can be considered for inclusion in the
general distribution of the kernel.

(See attached file: lockd_delay_patch.2.4.19)

Juan
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