Latest project I used Spring boot, and prepare to deploy to production environment, I want to know which way to run application have better performance or have the same performance?
generate a war package and put it in a stand-alone tomcat
generate a jar package and use embedded tomcat
In addition, when publish to production environment if should to remove devtools dependency.
This is a broad question. The answer is it depends on your requirements.
Personally, I prefer standalone applications with Spring Boot today. One app, one JVM. It gives you more flexibility and reliability in regard to deployments and runtime behaviour. Spring Boot 1.3.0.RELEASE comes with init scripts which allows you to run your Spring Boot application as a daemon on a Linux server. For instance, you can integrate rpm-maven-plugin into your build pipeline in order to package and publish your application as a RPM for deployment or you can dockerize your application easily.
With a classic deployment into a servlet container like Tomcat you will be facing various memory leaks after redeployment for example with logging frameworks, badly managed thread local objects, JDBC drivers and a lot more.
Either you spend time to fix all of those memory leaks inside your application and frameworks you use or just restart servlet container after a deployment. Running your application as a standalone version, you don't care about those memory leaks because you are forced to restart in order to bring you new version up.
In the past, several webapps ran inside one servlet container. This could lead to performance degradation for all webapps because every webapp has its own memory, cpu and GC characteristics which may interfere with each other. Further more, resources like thread pools were shared among all webapps.
In fact, a standalone application is not save from performance degradation due to high load on the server but it does not interfere with others in respect to memory utilization or GC. Keep in mind that performance or GC tuning is much more simpler if you can focus on the characteristics of just one application. It gets complicated as soon as you'll need to find common denominator for several webapps in one servlet container.
In the end, your decision may depend on your work environment. If you are building an application in a corporation where software is running and maintained by operations, it is more likely that you are forced to build a war. If you have the freedom to choose your deployment target, then I recommend a standalone application.
In order to remove devtools from a production build
you can use set the excludeDevtools build property to completely
remove the JAR. The property is supported with both the Maven and
Gradle plugins.
See Spring Boot documentation.
Related
Lets say I have 25 spring boot micro-services each of which starts with 1GB JVM in production. At any given time not all are in use and there is no instance when they are using the full 25GB memory at once. In reality many of them will sit idle 90% of the time but any of them might at some point get called and require up to 1GB memory.
In my development environment I would like to run all of them at once but only have 8GB memory. I don't need great performance but I need them all to run at the same time for the entire app to work. I would like to try to run all the applications within a single JVM with 6GB dedicated memory. That should be enough at any given time.
This seems like it would be a common issue as many companies are converting to cloud/microservices. 10 years ago we would have one monolithic app with single JVM (easy to run in dev environment). Now we have dozens of small apps which might not need a ton of memory but they each run in their own JVM so each has a good amount of overhead. This actually makes development more complex rather than simplifying. So Im trying to find a solution for our developers where they can run everything but not kill the memory on their machines.
The spring boot apps need to run without modification aside from
maybe local profiles. Otherwise developers would have to make tons of changes every time they pull the code from git
Each project needs to be able to configure a different port (application-local.properties setting)
for tomcat.
Each project needs its own classpath entries (for instance one might use version 1.0 of a jar and another might use version 2.0 and without separate classpaths one or the other would break)
I have been trying to follow this post but its not 100% what I want. I feel like a proper solution should respect the application.properties / application-local.properties file and use the port set inside the project rather than having to hardcode any configuration outside the project. Essentially his post is starting a separate thread for each microservice and attaching a separate classloader to each thread. Then calling SpringApplication.run and passing in the classname that would normally be used to start the microservice. I think this is maybe ignoring the auto configuration properties.
Any help would be greatly appreciated!
You can manage how much resources your applications are consuming with docker. One spring boot application should be one docker container. You can at runtime change how much resources(in your case memory) container use. Take a look at this
article on how to at runtime change resource allocation in docker. Also, with kubernetes is possible to define minimum and maximum resources that your application needs.
Our application are built on Spring boot, the app will be packaged to a war file and ran with java -jar xx.war -Dspring.profile=xxx. Generally the latest war package will served by a static web server like nginx.
Now we want to know if we can add auto-update for the application.
I have googled, and people suggested to use the Application server which support hot deployment, however we use spring boot as shown above.
I have thought to start a new thread once my application started, then check update and download the latest package. But I have to terminate the current application to start the new one since they use the same port, and if close the current app, the update thread will be terminated too.
So how to you handle this problem?
In my opinion that should be managed by some higher order dev-ops level orchestration system not by either the app nor its container. The decision to replace an app should not be at the dev-ops level and not the app level
One major advantage of spring-boot is the inversion of the traditional application-web-container to web-app model. As such the web container is usually (and best practice with Spring boot) built within the app itself. Hence it is fully self contained and crucially immutable. It therefore should not be the role of the app-web-container/web-app to replace either part-of or all-of itself.
Of course you can do whatever you like but you might find that the solution is not easy because it is not convention to do it in this way.
I Wanted to create Java EE application in JSF+Spring Framework with WildFly AS. One of the hot requirements is:
Plug and Play Modules This means if I update my application Or Add new module into my Application.
(Obviously Update bean.xml, web.xml, pojo classes , jars etc)
Then without redeployment of my *.war file and with out restarting my Wildfly AS changes occurs.
This is a complicated requirement for a few reasons. How will you handle changes to your DB schema/entity model? How will you handle sessions which are in progress at the time of the upgrade and are actively using the 'old' code? How do you handle changes to container managed code, code that is managed by the container only at deployment time, for example new EJBs etc?
One approach I have seen used in production to achieve some of these requirements is to do rolling updates with application versioning and full schema backwards compatibility. This is done in a clustered environment which is fronted by proxy servers that can allow active sessions using the old version of the application to continue until finished and ensure that new sessions go to servers/contexts containing the new version of the code. So you end up still deploying WARs which contain the new version of your code, and eventually undeploy the old versions when all old sessions have ended/expired. To do this you have to assume the burden in your code to fully support working against two simultaneous versions of your model when new versions introduce changes to it. This is not a trivial burden. You also have to assume the burden of the extra infrastructure to route sessions appropriately.
I know a product like JRebel will let you do hot deploys of code (even things like EJBs) with the idea being that it shortens the develop/test cycle but I haven't seen it used outside of a development environment. Also you would still have to deal with active sessions that were started on the old version /model.
More of a standard practice questions:
Is there any difference in deploying an app as EAR vs WAR? How do you decide? (I know WAR is just a web application may or may not have Java EE features like messaging)
Lets say I have a Spring MVC application stack with Hibernate (MySQL DB), should this be deployed as a War or EAR?
When do we need to worry about JBoss deployment descriptors, if I am not using EJBs. (Just Spring MVC). Lets assume I have JMS as well. Do we need to configure/update/create any other JBoss related config files?
When we package our application EAR/WAR, it include EVERYTHING that we need for our app. Is there a scenario where we need to keep some config / xml files outside of this archive in a specified JBoss folder?
Is it common practice to deploy directly from Eclipse or better to use Ant, etc? Advantage / Disadvantage?
Obviously, I am a newbie :-). Trying to understand this.
1.
This is not always an easy decision, but for beginners and for small projects I would say it's nearly always a WAR. The reason for using an EAR is mainly to isolate a business layer from a UI/Web layer. See this question for more details: How can one isolate logical layers of an Java EE application
2.
I might be mistaken but I think that Spring people typically prefer WARs.
3.
JBoss (vendor) specific deployment descriptors are mostly needed to configure so-called "administered objects" and security. Sometimes they can be used for extra features that are not covered by the Java EE specification (e.g. setting the web root for a WAR). Administered objects are typically data sources (connection to a database) and JMS destinations (queues and topics).
In the traditional Java EE approach these have to be created as far away from the code as possible, which typically means a system admin would create them inside the target AS using some kind of GUI or admin console. In this setup, you as developer would throw a WAR with "unresolved dependencies" over the wall, and a system admin (or "deployer") would then spend days figuring out what those unresolved dependencies should be.
If the communication is relatively good between developers and deployers, the WAR or EAR might be thrown over the wall together with a readme-file, that at least gives some insight into which resources are needed. Depending on the organization the development team might not get any access or feedback about how those "unresolved dependencies" have been resolved. E.g. a data source with a max of 5 connections may have been created, but this may be insufficient if some code does say 10 parallel queries. Without the development team knowing the exact data source configuration, some classes of runtime problems and performance issues may be relatively hard to solve.
To mitigate these problems, some vendors, for some artifacts, offer the developer to create those "unresolved dependencies" instead using proprietary deployment descriptors which are then embedded in the WAR or EAR. For simple local JMS destinations this is then in most cases the end of it, but for data sources there is a little bit more to it. Namely, there has to be a mechanism to switch between data sources for different stages such as Dev, Beta, QA, Production etc. Additionally, it's rarely a good idea to have production passwords in the source code.
If you have a simple app that you want to try out locally, stages and production passwords are not a concern. If you deploy for a (large) company it is.
In Java EE 6 you can define a data source using a standard descriptor (web.xml, ejb-jar.xml or application.xml), and in Java EE 7 you can do the same for JMS destinations. There is no standard way to configure those based on stage, but there is a glimmer of hope that Java EE 8 will address this (see e.g. JAVAEE_SPEC-19). Vendors are not universally happy with those standardized methods, and their main documentation will almost always extensibly tell you how to do those things using their proprietary tools and descriptors, and if you're lucky as a small note tell you there's a standardized way (and then sometimes downplay that or scare you by saying it's not recommended to be used in production).
4.
See answer to 3 mostly. One option to solve the problem of how to switch between stages and keep production passwords out of the WAR/EAR, is to have the full definition of said data source inside the AS (inside JBoss in your case). Every AS installation is tied to a specific server in this setup. If data sources need to be updated, removed or new ones added, you have to communicate with your operations team (if any). As said, depending on your organization this can be anything between trivial and practically impossible.
5.
When developing you most often use your IDE to do a deployment. For production you would never do that. For production you may build with Ant (or Maven) and deploy via something like Jenkins, or e.g Chef.
Check here : .war vs .ear file
If you read the preceeding response, you'd guess that "WAR" it is.
Deployment descriptor are needed to manage the modules of JBoss, if you don't have any conflict or don't need any tweaking, you won't need any deployment descriptor.
You may need to play with some JBoss file if you want to add modules to JBoss, or configure datasources, etc. Read the JBoss documentation for more info.
You can deploy from eclipse during your development phase, but as your other environments (qualification, production, test, etc) should be separeted from your developing one and that they won't have any eclipse installed on them, you should get used to manage your server from the command line and drop your war's in the right directories.
It's a short answer, but I hope it will help.
Read JBoss documentation for more info.
We are developing a open source trading platform based on Springframework and Hibernate http://code.google.com/p/algo-trader/ and http://www.algotrader.ch. The application consists of a trading framework and several strategies that can be started independently. So far, these different parts have been running in separate JVM's communicating through RMI and JMS.
To avoid unnecessary serialization and network overhead we would like to run the entire application within some sort of container (potentially an application server). We do however have the requirement, that the individual parts of the application can be deployed, started and stopped independently.
We have looked into OSGi, but a lot of the libraries that we use are not OSGi ready yet, so this is not currently an option. Also please note, there is no web-GUI in our application.
Any suggestions on this?
Thanks
Andy
If OSGI is not an option then functionality can be broken into smaller units and then deploy them as utility jar, if deployed as utility jar they can be managed independently.
For application server I feel either glassfish or Jboss will be a good option considering they are open source and free.
Though at a later point in time you can check with Weblogic (Dev free).
So in your case you would like to break the static data configuration(Counterparty, Currencies), Dealing(Pricing, Quoting, Booking) as two separate feature.
For your choose of an application server i advise you Jboss and specially in his version 7.1 which is faster and more stable!