NanoCloud – cloud scale JVM

Alexey Ragozin

Feb 2014

Long time ago …

2009 – building Coherence demo for Amazon EC2• hybrid HPC / DHT cluster• a lot of debugging required• single button deployment

2009 – 2014 – developing cluster applications• demand to test distributed cases locally• Singleton syndrome of Coherence and GemFire

Distributed object paradigm

CORBA, RMI• Exposed remote interfaces

Interface is functional contract Remote protocol is NFR driven implementation

• Heavy infrastructure Brokers Complex connectivity topology

Remoting by convention

If object is “remotable” interface,It would be converted to remote stub

When passing between process boundaries

“remotable” object could be as deep in object graph as you like

stub resolved to object if passed back

Encapsulating RPC

Wrapper class• Implements functional contract• Has private instance of remotable service

Remote service• Not exposed beyond wrapper class• Managed by wrapper class• Automatically exported if wrapper class instance is

transferred to another process

Encapsulating RPC

PRO+ Decoupling of functional and remote contracts+ Consistent local/remote behaviorCON– Homogenous codebase required– Synchronous RPC syndrome is not addressed

OutputStream

NanoCloud’s Zero RMI

Own implementation of RMI Standard Java serialization Serializing of anonymous Runnable/Callable

Auto export of Remote interfaces during serialization of object graph

Single communication socket

Bidirectional communications

public interface RemotePut extends Remote { public void put(Object key, Object value); }

RemotePut remoteService = client1.exec(new Callable<RemotePut>() { @Override public RemotePut call() { final NamedCache cache = CacheFactory.getCache(cacheName); return new RemotePut() { @Override public void put(Object key, Object value) { cache.put(key, value); } }; }});

public interface RemotePut extends Remote { public void put(Object key, Object value); }

@SuppressWarnings("unused")@Testpublic void bidirectional_remoting() { // Present for typical single node cluster cloud.all().presetFastLocalCluster(); cloud.node("storage.**").localStorage(true); cloud.node("client.**").localStorage(false); // Simulates DefaultCacheServer based process cloud.node("storage.**").autoStartServices(); // declaring specific nodes to be created CohNode storage = cloud.node("storage.1"); CohNode client1 = cloud.node("client.1"); CohNode client2 = cloud.node("client.2"); // now we have 3 specific nodes in cloud // all of then will be initialized in parallel cloud.all().ensureCluster();

final String cacheName = "distr-a"; RemotePut remoteService = client1.exec(new Callable<RemotePut>() { @Override public RemotePut call() { final NamedCache cache = CacheFactory.getCache(cacheName); return new RemotePut() { @Override public void put(Object key, Object value) { cache.put(key, value); } }; } });

remoteService.put("A", "aaa"); client2.exec(new Runnable() { @Override public void run() { NamedCache cache = CacheFactory.getCache(cacheName); Assert.assertEquals("aaa", cache.get("A")); } });}

remoteService.put("A", "aaa");

Bidirectional communications

public interface RemotePut extends Remote { public void put(Object key, Object value); }

RemotePut remoteService = client1.exec(new Callable<RemotePut>() { @Override public RemotePut call() { final NamedCache cache = CacheFactory.getCache(cacheName); return new RemotePut() { @Override public void put(Object key, Object value) { cache.put(key, value); } }; }});

remoteService.put("A", "aaa");

Extending java.rmi.Remotexec will mark interface for auto export

Unlike Java RMI, there is no need to declare RemoteException for every method

Result of callable will be serialized and transferred to caller

Objects implementing remote interfaces are automatically replaced with remote stub during serialization

Here we got a remote stub, not a real implementation of interface

Call to a stub, will be converted to “remote” call to instance we have created in “virtualized” node few lines above

Casual provisioning

Normally you would• build and package your code• deploy / copy code artifact• go to server via SSH console

in worst case – to each of your servers

• start your processes via some script• repeat 20-30 times per day• configuration aspects are not considered

a lot of spare time while your file are crossing Atlantic

Casual provisioning

What NanoCloud will do for you?• Package your runtime classpath• Copy changed artifacts via SFTP• Start remote process via SSH• Do all RMI configuration/handshaking• Route console output to you• … and kill slave process once your are done

No more coffee breaks. Turn around in few seconds.

As easy as …

@Test public void remote_hello_world() throws InterruptedException { ViManager cloud = CloudFactory.createSimpleSshCloud(); cloud.node("myserver.uk.db.com"); cloud.node("**").exec(new Callable<Void>() { @Override public Void call() throws Exception { String localHost = InetAddress.getLocalHost().toString(); System.out.println("Hi! I'm running on " + localHost); return null; } }); }

All you need is …

NanoCloud requirementsSSHdJava (1.6 and above) present

Works though NAT and firewallsWorks on Amazon EC2Works everywhere where SSH works

Master – slave communications

Master process Slave hostSSH(Single TCP)

Slave

Slave

RMI(TCP)

std err

std out

std in

diag

Slavecontroller

Slavecontroller

multiplexed slave streams Agent

Death clock is ticking

Master JVM kills slave processes, unless SSH session was interrupted someone kill -9 master JVM master JVM has crashed (e.g. under debuger)Death clock is ticking on slave though if master is not responding slave process will terminate itself

No zombies allowed

Cloud scale JVM

Same API – different topoligies in-process (debug), local, remote (distributed)

Transparent remotingSSH to manage remote serverAutomatic classpath replication (with caching)Zero infrastructure

Any OS for master host SSHd + JVM for slave hosts

200+ slave topology in routinely used

Road map

NanoCloud 0.7.23• 0.7.X in used since Mar 2013• Last fix Sep 2013

NanoCloud 0.8.2 – unstable (stable ETA 2014 Q3)• Programmatic console stream access• Byte code instrumentation• JVM version verification• Option NOT to use Java SSH client (planned)• Consistent error reporting (planned)

Sneak peek: Instrumentation

System.exit() – is still fatal Some cases need “virtual time” Tweaking monolithic code Fault injection Mock injection

Sneak peek: Instrumentation

PowerMock Recompiles everything (Coherence ～ 5000

classes)

AspectJ Static interceptorsByteMan Using agent + weird language

Sneak peek: Instrumentation

ViNode node = ...

ViHookBuilder.newCallSiteHook().onTypes(System.class).onMethod("exit").doReturn(null).apply(node);

node.exec(new Callable<Void>() {@Overridepublic Void call() throws Exception {

System.exit(0);return null;

}});

API is subject to change

New opportunities

Performance testing deploy system under test deploy load generators deploy monitoring agents gather all result in one place

Deployment (remote execution task for ANT)Replace your putty with Java IDE log scrapping parallel execution

Coding for 200+ processes

Driver - concept• Driver – Java interface encapsulates test

action• One way methods• Friendly for remotting for parallel invokation+ some utility for parallel execution, workflow

etcExample:

https://gridkit.googlecode.com/svn/grid-lab/trunk/examples/zk-benchmark-sample

Links

NanoCloud• https://code.google.com/p/gridkit/wiki/NanoCloudTutorial• Maven Central: org.gridkit.lab:telecontrol-ssh:0.7.23• http://blog.ragozin.info/2013/01/remote-code-execution-in-java-made.html

ANT task• https://github.com/gridkit/gridant

ChTest (Coherence test tool)• https://code.google.com/p/gridkit/wiki/ChTest• Maven Central: org.gridkit.coherence-tools:chtest:0.2.4

Thank you

Alexey Ragozin alexey.ragozin@gmail.com

http://blog.ragozin.info- my articleshttp://code.google.com/p/gridkithttp://github.com/gridkit- my open source codehttp://aragozin.timepad.ru- community events in Moscow

Managing artifacts

… a bunch of black magic to find local repoand managing classpath as easy as …

<plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-dependency-plugin</artifactId> <version>2.8</version> <executions> <execution> <id>viconcurrent-0.7.15</id> <phase>test-compile</phase> <goals> <goal>get</goal> </goals> <configuration> <artifact>org.gridkit.lab:viconcurrent:0.7.15</artifact> </configuration> </execution> </executions></plugin>

Managing artifacts

How to get needed artifact on local disk- Maven will disallow two versions of same artifact- but we can trick it …

Transitive dependencies are not included, though.

ViNode node;…node.x(MAVEN).replace("org.gridkit.lab", "viconcurrent", "0.7.15");