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title: PSI/J
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						<h2>Portable Submission Interface for Jobs</h2>
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					<p>
						PSI/J is a portability layer across different HPC workload managers allowing workflow developers
						and users to create portable workflows with a standard API. PSI/J aims to focus effort by
						pooling into a single layer the collective knowledge obtained from these disparate efforts.
						PSI/J is composed of both a language-agnostic community-defined specification and the
						specification's <a href="https://github.com/ExaWorks/job-api-spec"
							target="_blank">language-specific implementations</a>. The high-level goals of the
						specification are to be lightweight, user-space, minimally prescriptive, scalable via
						asynchronous operations, general, and extensible to different systems, schedulers,
						implementations.
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					<p>
						The PSI/J specification is broken into three layers that each build on one another:
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						<li>The first layer forms the base of the specification and focuses on supporting the launching
							and monitoring of "<strong>local</strong>" jobs (i.e., the client is running on the same system or cluster as
							the jobs).</li>
						<li>The second layer builds on the first to provide support for "<strong>remote</strong>" jobs (i.e., the client
							must connect over the network, potentially with authentication, to launch and monitor jobs),
							managing multiple clusters simultaneously, and allowing file staging.</li>
						<li>The third layer builds on the previous two to support efficient execution of small jobs
							through the "nested", "<strong>pilot job</strong>", or "jobs-in-jobs" paradigm.</li>
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