/sys$common/syshlp/helplib.hlb Sys Parameters, ERRORLOGBUFFERS  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    ERRORLOGBUFFERS specifies the number of buffers reserved for
    system error log entries. Each buffer is ERLBUFFERPAGES in
    length. If ERRORLOGBUFFERS is too low, messages might not be
    written to the error log file. If it is too high, unneeded
    physical pages can be consumed by the error log buffers.

    If you increase ERRORLOGBUFFERS, you must also increase the size
    of the system dump file.