If you see below "command" is missing "callpool" argument, while it states that it should be provided but the example output doesn't have it this would confuse people. 

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Display the pending calls of the volume using the following command:
# gluster volume status VOLNAME callpool
Each call has a call stack containing call frames.
For example, to display the pending calls of test-volume:
# gluster volume status test-volume

Pending calls for volume test-volume
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Brick : arch:/export/1
Pending calls: 2
Call Stack1
 UID    : 0
 GID    : 0
 PID    : 26338
 Unique : 192138
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