Add build instructions

Author: AntonKozlov

README.md

@@ -1,3 +1,38 @@
 # example-spring-boot
 
-From https://github.com/spring-guides/gs-spring-boot, directory "initial"
+## Building
+
+1. Create once a [Personal Access Token (PAK)](https://docs.github.com/en/github/authenticating-to-github/creating-a-personal-access-token) with [packages scope](https://docs.github.com/en/packages/publishing-and-managing-packages/about-github-packages#about-tokens).
+2. Provide the PAK in the environment
+```
+export GITHUB_ACTOR=YOUR_USERNAME
+export GITHUB_TOKEN=YOUR_PAK
+```
+3. Use maven to build
+```
+mvn -s settings.xml package
+```
+
+## Running
+
+Please refer to [README](https://github.com/org-crac/docs#users-flow) for details.
+
+### Preparing the image
+1. Run the [JDK](README.md#JDK) in the checkpoint mode
+```
+$JAVA_HOME/bin/java -Zcheckpoint:cr -jar target/spring-boot-0.0.1-SNAPSHOT.jar
+```
+2. Warm-up the instance
+```
+siege -c 1 -r 100000 -b -H "Content-type: text/plain" "http://localhost:8080/transform POST < example.xml"
+```
+3. Request checkpoint
+```
+jcmd target/spring-boot-0.0.1-SNAPSHOT.jar JDK.checkpoint
+```
+
+### Restoring
+
+```
+$JAVA_HOME/bin/java -Zrestore:cr
+```