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The private QOS signifies a willingness to have your job flagged as pre-emptable (cancellable by hardware owners) as a trade-off for being able to use that privately owned resource longer than the protected four-hour htc partition offering. This can sometimes greatly reduce the time-to-start for jobs, but is heavily dependent on the aggregate supercomputer load. Pre-emptable jobs will be canceled if and only if the private owners submit a job to those resources.
Examples of this might be to use privately owned GPUs, especially where checkpointing is used.
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