VMS Help V73 Features, Programming Features, SDA Commands for Spinlock Tracing, SPL_START_TRACE  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    This command enables spinlock tracing. Qualifiers for the SPL
    START TRACE Command shows the qualifiers for this command.

    Table 5-5 Qualifiers for the SPL START TRACE Command

    Qualifier          Meaning

    /SPINLOCK=spinlock Specifies the tracing of a specific spinlock.
    /NOSPINLOCK        Disables spinlock tracing and does not collect
                       any spinlock data. If omitted, all spinlocks
                       are traced.
    /FORKLOCK=forklock Specifies the tracing of a specific
                       forklock, for example, /FORKLOCK=IOLOCK8 or
                       /FORKLOCK=IPL8.
    /NOFORKLOCK        Disables forklock tracing and does not collect
                       any forklock data. If omitted, all forks are
                       traced.
    /BUFFER=pages      Specifies the size of the trace buffer (in
                       Alpha page units). It defaults to 128 pages,
                       which is equivalent to 1MB, if omitted.
    /ACQUIRE           Traces any spinlock acquisitions. This is the
                       default.
    /NOACQUIRE         Ignores any spinlock acquisitions.
    /RELEASE           Traces any spinlock releases. This is the
                       default.
    /NORELEASE         Ignores any spinlock releases.
    /WAIT              Traces any spinwait operations. This is the
                       default.
    /NOWAIT            Ignores any spinwait operations.
    /FRKDSPTH          Traces all invocations of fork routines within
                       the fork dispatcher. This is the default.
    /NOFRKDSPTH        Ignores all of the /FRKDSPTH operations.
    /FRKEND            Traces all returns from fork routines within
                       the fork dispatcher. This is the default.
    /NOFRKEND          Ignores all of the operations of the /FRKEND
                       qualifier.
    /CPU=n             Specifies the tracing of a specific CPU
                       only, for example, /CPU=5 or /CPU=PRIMARY.
                       By default, all CPUs are traced.