As we near the release of Alfresco Enterprise Edition 5.0, Community Edition has evolved a lot. Community Edition 5.0.a was an opportunity for the Engineering team to get feedback on the improvements in the 5.0 source tree. Though it was a solid release, there was still a lot of new development to complete on the road to an Enterprise Edition release. The Engineering team has now adopted a policy of only doing bug fixes on the 5.0 source tree, and Community Edition 5.0.b contains the rest of what we plan for 5.0. There are a lot of under-the-hood enhancements. The release notes mention that Solr4 is required for full functionality (goodbye Lucene), and the location of many configuration files have changed. Deprecated components such as the AVM and the Explorer UI are finally being removed. This blog post documents a small changes that caught me off guard.
When installing 5.0.b, the installer now does additional checks of the environment to verify that it is capable of reliably running Alfresco. I got this error:
CPU clock speed of 1.19 GHz is slower than the minimum required by Alfresco (1.2 GHz). Alfresco will not perform well. Upgrade the server to one with more modern CPUs (CPU clock speed of at least 1.2 GHz, and preferably 2.0 GHz or more).
This is surprising because my laptop contains an Intel i7 Q 820 with 8 cores running at 1.73GHz.
The root of the problem is CPU frequency scaling, otherwise known as CPU throttling. When I first start the installer, my laptop isn't under any sort of load so it saves energy by scaling itself back to 1.19 GHz.
This can be disabled in the BIOS (on a ThinkPad it's under CPU Power Profile). It can also be temporarily disabled on Linux by using the "cpupower" utility that comes in the "tools" directory of modern kernels (on Fedora 20 it is found in the kernel-tools package). On many distributions, the CPU governor policy defaults to "ondemand". Change it to "performance" with this command:
sudo cpupower frequency-set -g performance
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