Open Source Summit North America 2022

In serverless environments it is desirable to have applications that can startup very quickly. Very fast startup can enable scale to zero when deploying applications to Kubernetes with technologies like Knative. Many popular Java frameworks have looked to using native compilation using GraalVM with the Substrate native compiler to achieve very fast startup. For many Java applications compiling to native is quite difficult and often times not possible without large amounts of effort. In this talk Tom will discuss another approach that uses Linux Checkout/Restore (CRIU). CRIU is a feature on Linux that enables a snapshot of a running application to be taken. This snapshot can be restored very quickly from the point the snapshot was taken. One advantage of this approach is that once the application is restored it is business as usual for the application. All the functionality of a normal Java environment are available to the application once it is restored. No additional changes should be necessary for the application to take advantage of the instant on functionality provided by CRIU. Tom will discuss the work the Eclipse OpenJ9 and Open Liberty projects are doing to safely be able to use Checkpoint/Restore for achieving "instant on" for Java Applications.