By pcr on Jan 05, 2005
An email for from a friend today asked the question "What do you suggest to help a programmer understand Solaris Memory internals?" I thought about it and suggested Richard McDougall and Jim Mauro's book Solaris Internals. However, that book is a perfect illustration of my theory of the "half life of information." The book was released in the year 2000 and covered Solaris 7. Mssrs. McDougall, Leventhal, Cantrill, Bonwick, Price, Shrock et al. have been extremely busy and much improved Solaris from the days of priority paging in Solaris 7. In Solaris 8 and beyond the page scanning algorithm is now called Cyclical Page Cache so the book is outdated in some respects. The term 'half life' is drawn from radioactivity and refers to "the length of time in which half the nuclei of a species of radioactive substance would decay." The image of 'information half life' is how much of the material in the book from 2000 is still accurate. My belief is that much of the material in the book is still relevant since the early architecture of Solaris has carried through to Solaris 10 (download and play with your copy from here.) The information in the book has been updated for later versions of Solaris (8 to 10) in a set of 367 slides, dated November, 2004, in an Adobe acrobat file available here. Those of you on dialup do not want to download that file and you are already mad at me because of the number of images on my page.
And in a late breaking update, Richard just asked me to review the new chapters for Solaris 10. Hope that the publisher can get the revised version out soon so the information half life will be longer.