If you click on the image, it'll expand into something more easily read. But don't.
January 2012 was not a good month for ICPSR's web delivery system, We missed our monthly goal of 99%+ availability. Not by a lot, but still missed it.
Many of the problems this month are related to an upgrade we made to our delivery infrastructure. We replaced a five-year-old 32-bit machine with a new 64-bit machine with significantly more memory and processing power. And we upgraded from an older version of tomcat to the latest release.
The maintenance itself accounted for less than an hour of downtime, but various issues related to the upgrade brought additional short periods of downtime. A "death by a thousand cuts" sort of thing.
The good news if that the reliability and stability of the system now seems better, and the upgrade has exposed a couple of software flaws that we have been able to correct. It also has eliminated the last of the 32-bit systems from ICPSR, and so we are less likely to run into problems where we (accidentally) try to run 64-bit binaries and libraries on 32-bit machines.