Hello,
There were some improvements to the Linaro Android Build Service (aka linaro-cloud-buildd), https://android-build.linaro.org/ . The Jenkins EC2 plugin was upgraded to the latest version 1.11, which should improve EC2 instance management. There was also fixed a bug which caused unreliable build process in case an instance was reused to build different configurations.
While working towards completely disposable build instances (which would require patching Jenkins/EC2 plugin), these changes should allow for sustainable build reliability in the meantime. There were around a dozen builds since these changes, and none of them showed infrastructure failures. I hope it now will be easier to concentrate on actual build failures where they happen.
The Android Build Service documentation is available at https://wiki.linaro.org/Platform/Android/LinaroAndroidBuildService
Thanks, Paul