/CONFIGURE=(NAME=name [,CREDENTIALS=credentials]
       [,FACILITY=facility] [,FILE=file] [,THREAD_MAX=n][,...])

    Dynamically loads an ACME agent. An ACME agent is a shareable
    image that conforms to the ACME agent plug-in interface
    specification.

    By default, the ACME server looks for an ACME agent file named
    prefix$name_ACMESHR.EXE, where the prefix is VMS by default
    and name is the case-insensitive string specified by the NAME
    keyword. The prefix can be overridden by the FACILITY keyword.
    Otherwise, a complete file specification can be specified with
    the FILE keyword.

    You must specify the CREDENTIALS keyword if the ACME agent is a
    domain of interpretation (DOI) agent capable of authenticating
    users and issuing credentials. The CREDENTIALS keyword specifies
    the name of the persona extension associated with the ACME
    agent (see the $PERSONA_EXTENSION_LOOKUP system service). The
    credentials name must match the name registered by the executive
    loadable image that implements the persona extension. For
    credentials other than "VMS", see the documentation provided
    for the ACME agent and the specific persona extension.

    A maximum of eight ACME agents can be configured.

    THREAD_MAX Keyword: Usage Considerations

    An ACME server worker thread is the authentication request
    processing thread of execution. The number of worker threads
    determines the number of authentication requests the ACME server
    can process simultaneously.

    The ACME server assigns a request slot to each in-progress
    authentication request. The total number of request slots sets
    a limit on the maximum number of requests the ACME server can
    have outstanding.

    The ACME server limits the number of unprivileged authentication
    requests it can accept for processing to half the total number of
    request slots.

    If a process makes a call to $ACM and no request slots are
    available, the process remains in resource wait state until a
    request slot becomes free.

    The number of ACME server worker threads can range from 1 to 32.
    The default of 4 satisfies most operating environments in which
    authentication processing time is largely spent waiting for I/O.
    You may, however, be able to improve throughput by increasing the
    number of worker threads if, for example, you have a user-written
    ACME agent that requires more CPU time than most.

    You can set the maximum number of ACME server worker threads
    before you start or restart the server by defining the inner-mode
    logical name ACME$THREAD_MAXIMUM in the system-wide logical name
    table. For example:

    $ DEFINE/SYSTEM/EXECUTIVE_MODE ACME$THREAD_MAXIMUM 8

    You can also use the CONFIGURE qualifier to set the maximum
    number of server worker threads before you enable the ACME
    server. For example:

    $ SET SERVER ACME /CONFIGURE=THREAD_MAX=6

    The CONFIGURE qualifier overrides the value of the ACME$THREAD_
    MAXIMUM logical, if it is defined.

    Because most authentication processing is I/O bound, defining
    more threads than about one quarter the number of request slots
    does not gain more throughput.

    The ACME server calculates a default number of request slots
    from the value of MAXPROCESSCNT and the number of available CPUs.
    You can override the calculated value by defining the inner-mode
    logical name ACME$REQUEST_MAXIMUM in the system-wide name table
    before you start or restart the ACME server. For example:

    $ DEFINE /SYSTEM /EXECUTIVE_MODE ACME$REQUEST_MAXIMUM 64
    $ SET SERVER ACME /RESTART