Message from WoSAR 2012 Workshop Chairs

This volume contains the papers presented at the Fourth International Workshop on Software Aging and Rejuvenation (WoSAR) held November, 29th 2012 at Dallas, USA. This year, we had Kenny Gross and Yen-Nun Huang as keynote speakers. Kenny Gross, Distinguished Engineer from Oracle, presented a talk on"Integration of Electronic Prognostics with Software Aging and Rejuvenation for Business-Critical Enterprise Servers." Yen-Nun Huang, CEO of Security Research Center from Academia Sinica, shared with us the subject "Software Rejuvenation: How was it invented and why is it important today?" The workshop aims at gathering experts from industry and academia working on both theoretical and applied aspects of software aging and rejuvenation. Given this objective we are happy with the accepted papers this year that widely cover many important areas of Software Aging and Rejuvenation. Besides keynote sessions the program consists of three technical sessions. The first technical session presents Experimental Studies on software aging and rejuvenation. The second technical session presents the Rejuvenation Modeling to different types of systems, and the third technical session presents Applications of Rejuvenation.