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  1. OMG Issue

PSS — PSS FTF issue: PSS & Thread-Safety

  • Key: PSS-14
  • Legacy Issue Number: 3186
  • Status: closed  
  • Source: ZeroC ( Bernard Normier)
  • Summary:

    The Persistent State Service draft specification does not say anything
    about thread-safety. For portability, it is necessary to define the
    guarantees provided by a thread-safe PSS implementation.

    A catalog (session or session pool) can be either thread-safe or
    thread-unsafe. A compliant implementation does not need to provide
    thread-safe catalogs.
    All objects provided directly or indirectly by a thread-unsafe
    catalog are thread-unsafe – the application must serialize access
    to any of these objects, typically by using a single thread.

    (1) A storage object incarnation provided by a thread-safe catalog
    is like a struct: concurrent reads are safe and do not require any
    locking by the application; concurrent writes (or a concurrent
    read and a concurrent write) are not thread-safe – the application
    must ensure mutual exclusion to avoid problems.
    Flushing a storage object is like reading this object. 'Refreshing'
    a storage object is like updating it.

    (2) Further, the following Session operations are not thread safe:
    they are not supposed to be called concurrently, and no thread
    should be using the target session (or anything in the target
    session, such as an incarnation or a storage home) when they are


    OTS operations are however safe; for example one thread can call
    tx_current->rollback() while another thread calls start, suspend or
    end on a session involved in this transaction, or while a thread
    is using storage objects managed by that session.

  • Reported: PSS 1.0b1 — Fri, 7 Jan 2000 05:00 GMT
  • Disposition: Resolved — PSS 1.0
  • Disposition Summary:


  • Updated: Fri, 6 Mar 2015 20:58 GMT