JarCastingFalchion
Falchion is an antifragile JVM container. Falchion container requires JDK9 because it's using SO_REUSEPORT flag. JDK9 supports SO_REUSEPORT only on Linux.
When the container has started, it forks JVM processes until the given pool size. If the container catch a HUP signal, it creates a new JVM processes and kill old processes.
Usage
Download the falchion script and run.
% falchion [mainClass] -cp classpath
Options
- -cp Classpath
- -basedir The base directory of jar files
- -v application version
- -p The pool size of JVM processes. (default value is 1)
- --lifetime LIFETIME SECONDS The lifetime of one jvm process. If you set the option to 3600, container will kill all old JVMs and create new JVMs gracefully.
- -m MONITORS Adds monitors for monitoring a jvm process. Available monitors:
- JSTAT_GCUTIL GC statistics using jstat
- METRICS_JMX Metrics using JMX
- --auto-tuning tuning JVM parameters automatically.
- --evaluator EVALUATOR
When using the options "-basedir" and "-v", Falchion container generates classpath using basedir and aplVersion. Please set the folder hierarchy like the example below.
- applicationBaseDir <- basedir
- 0.1.0 <- application version
- applicationA.jar
- applicationB.jar
- subDir
- applicationC.jar
- 0.1.1
- 0.1.0 <- application version
REST API
Falchion container provides HTTP APIs for getting the information of JVM processes or refreshing JVM processes.
GET /jvms
% curl -i http://localhost:44010/jvms
HTTP/1.1 200 OK
Date: Mon, 02 May 2016 10:11:24 GMT
Content-type: application/json
Content-length: 28
[{"id":"5jiic","pid":21914}]
GET /jvm/{id}
% curl -i http://localhost:44010/jvm/5jiic
HTTP/1.1 200 OK
Date: Mon, 02 May 2016 10:12:23 GMT
Content-type: application/json
Content-length: 182
{"id":"5jiic","pid":21914,"uptime":258357,"stats":[{"type":"gcutil","S0":0.0,"S1":100.0,"E":16.88,"O":3.1,"M":94.86,"CCS":80.13,"YGC":1,"YGCT":0.004,"FGC":0,"FGCT":0.0,"GCT":0.004}]}
POST /container/refresh
Kill all old JVMs and create new JVMs gracefully.
POST /container/refresh/{version}
Kill all old JVMs and create new JVMs gracefully. Change classpath using new version.
Auto tuning
Falchion can optimize JVM options automatically.