From: Tristan C Collier <[log in to unmask]> Date: Fri, 17 Feb 2012 14:11:41 +0000 Dear All, Further to our previous message, we can now provide more detail. The performance problems experienced on CJO this week are due to corruption in the access control cache system. This is a critical part of the CJO system - just about every page checks access - and is fundamental to adequate site performance. If we have corruption the system bypasses this cache and the load increases significantly causing the slowdown and outages experienced by some customers. In terms of immediate actions we either have done or are planning the following: 1. On Wednesday 15th February, after the most significant set of problems, we amended a number of application settings. This has stabilised the situation allowing us to continue with further work on the system without affecting users. 2. We will need to rebuild the access cache and we are planning to do this over the coming weekend (18th & 19th February). This is a slow and quite system intensive process, taking more than 24 hours, hence needing to wait for a weekend to run it. The support teams have met today (17th February) to finalise the details for this work. It is not anticipated that customers will experience any slow running as a result of this process, as we will work through this offline and introduce the changes to the live site on Monday 20th. 3. The support team are investigating ways of improving the access cache system to avoid this problem in the future. An initial piece of this work has already been developed and is due for deployment in a week’s time. Once again, please accept our apologies for any inconvenience that has been caused. Also thanks again to all in the library community who have provided valuable feedback. Kind regards Cambridge Journals Cambridge University Press University Printing House Shaftesbury Road Cambridge, CB2 8BS England, UK http://www.journals.cambridge.org