Generic NQS Protocol
Background Information
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Designed in 1985, NASA's original COSMIC NQS uses an application-layer
network protocol which relies on the binary encoding of information, and
on fixed-format messages. This protocol was reverse-engineered by Cray
Research, Inc, and is available from them as "NQS Networking Protocol Specification".
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This protocol suffers from a number of problems.
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The binary encoding makes it difficult to port the implementation of the
protocol to new architectures. While the existing implementation within
Generic NQS works fine on both 32-bit and 64-bit architectures, it cannot
be guarenteed that it will work on whatever size architecture comes next
...
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The protocol cannot be extended - obviously it can be extended in the traditional
way, by adding new message types, but a) these extensions are proprietry,
and b) what really needs to be done is to extend an existing message (support
for DCE and AFS is a case in point).
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Finally, the protocol is completely specific to the NQS family of products,
and is not suitable for use in non-NQS products.
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The core NQS user commands are as follows:
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qsub - Submit an NQS job
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qdel - Delete an NQS job
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qstat - Determine the status of a job or a queue
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qcat - Look at the output of running jobs
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Advanced Information:
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Qhold - Qhold holds all queued or waiting NQS requests given on the command
line. Qhold will not hold a running request.
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Qrls - Qrls is the inverse operation of Qhold. That is, it releases a held
request and makes it eligible to be scheduled to run. Qrls will cannot
release a job which is not being held.
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Qsuspend - Qsuspend takes a running request and causes it to have no access
to the cpu. That is, it will no longer run. One cannot suspend a request
which is not in the NQS Running state.
Qresume - Qresume is the inverse operation of Qsuspend. It takes a
suspended job and lets the cpu run the job again. Qresume cannot resume
a job which is not suspended.
Qlimit - Qlimit does not modify the request, but shows the supported
batch limits and shell strategy for the local or remote host.
Last Updated: 5th September 1997 by Mark
Baker