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The whole site on one page, grouped the way the navigation groups it, plus the machine-readable indexes.

Using CRaC

Overview The deployment scheme CRaC implies: warm an application up, take an image, ship the image.
Runtimes with CRaC CRaC has to be built into the Java runtime. The upstream builds, the vendor builds, and the criu permissions they need.
Checkpoint and restore Taking a checkpoint of a running JVM and restoring from the image.
Implementing the API Using org.crac to release and reacquire the resources a checkpoint cannot carry.

Overview Frameworks and libraries that coordinate with CRaC, so an application inherits the coordination.
Spring Boot CRaC support in Spring Boot and Spring Framework.
Quarkus CRaC support in Quarkus.
Micronaut The Micronaut CRaC module and its build plugin.
AWS Lambda Running CRaC-aware Java functions on AWS Lambda.

Complete applications that take a checkpoint and restore from it.

Overview The things you need once CRaC is working: what to avoid, how to diagnose a failed checkpoint, and how file descriptors and CPU features are handled.
Best practices What to do and what to avoid when writing an application that will be checkpointed.
Checkpoint engines Choosing the mechanism that takes the image, with -XX:CRaCEngine — what upstream ships, and what a vendor build may add.
Debugging failures Diagnosing a checkpoint or restore that did not work.
File descriptor policies Telling the runtime what to do with each open file descriptor at checkpoint time.
CPU features Why a restored image is tied to CPU features, and how to control that.

The project What the CRaC project is, who sponsors it, and where the work happens.
What CRaC is How checkpoint and restore work, what the API is for, and what a Java application has to coordinate.
Measured results Time to first operation, cold start against restore, as measured by the project — with the conditions they were measured under.

For machines

Both generated from the same content as the pages above.