The OpenVMS Internals and Data Structures Manual (IDSM) is available
from Digital Press -- this manual contains the details of the internal
design of OpenVMS -- IPL, spinlocks, memory management, etc. Editions
for OpenVMS VAX and OpenVMS Alpha are available.
US & Canada URL http://www.bh.com/bh/dp
UK & Europe URL http://www.butterworth.heinemann.co.uk
General programming information on IPL and memory management is covered
in the processor manual (for the physical memory layout) for the system
in use, in the architecture reference manual (versions are available for
VAX and Alpha), and in the device driver manual set -- device driver
manual sets are available for OpenVMS VAX and OpenVMS Alpha.