| Hi Øyvind I certainly referred to Bill Roscoe's second book on CSP, which he describes as part sequel, part successor, to his original Theory and Practice of Concurrency : Roscoe, A. W. : 2010, Understanding Concurrent Systems, Springer ISBN 978-1-84882-257-3 I mentioned the one section on priority in the book (#20.2 Priority, pp. 486-496 (though there is a brief mention earlier in the context of timed systems), where he rejects prioritised choice (PRI ALT) because it presents problems "when the priority orders of different parallel processes cannot be resolved". I managed a brief chat with Gavin Lowe, whose thesis concerned prioritisation, and suggested I really ought perhaps to read his thesis first. He recommended instead starting with his more recent papers, as they were more up-to-date. From these contributions, this discussion (thread), and my own thoughts, I think there are two clear conclusions thus far : 1 in the presence of many low-cost processors ('cores'), we can usually forget prioritisation in practice 2 where a programming language does incorporate prioritisation, it is better to prioritise events (and their response), in which case there must be an opportunity to declare a partial order over the events concerned over the scope affected. I remain concerned that the first approach may sometimes result in a more complicated communication pattern which may be more difficult to program (or, conversely, invite more error). I have yet to fully understand the consensus (if there is one) in the CSP community over programming prioritisation. Ian On 4 Oct 2012, at 08:13, Teig, Oyvind CCS wrote:
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