For Alpha Galaxy systems, GLX_SHM_REG is the number of shared memory region structures configured into the Galaxy Management Database (GMDB). If set to 0, the default number of shared memory regions are configured. If the condition value SS$_INSF_SHM_REG is returned for the $CRNMPSC_GDZRO_64 system service with the flag SEC$M_SHM_REG, the Galaxy shared memory code has run out of internal SHM_REG data structures. You need to increase the system parameter GLX_SHM_REG and reboot all Galaxy instances with this larger parameter value.