I've got an application that uses Spring Cache (Ehcache), but now we need to add a 2nd node (same application). Can the cache be shared between the nodes or each with their own instance but synched?
Or do I need to look at a different solution?
Thanks.
That depends on your cache implementation - not on Spring, which only provides an abstract caching API. You are using EhCache as your caching implementation, which comes with a Terracotta server for basic clustering support and is open source. See http://www.ehcache.org/documentation/3.1/clustered-cache.html#clustering-concepts for more details
Related
We have a solution which uses the Apache Ignite-provided In-Memory Data Grid as a distributed cache. For newer projects, we ended up using Spring, and as such we wished homogenize our software ecosystem and using Spring for the first solution as well. In addition, we do not use all the features of Ignite to excuse its use (discovery, caching).
Since we currently only use a limited subset of features from Ignite, we are basically looking for a self-managed application-level distributed cache solution (similar to what Ignite provides). This means that dedicated caching infrastructure like Redis, Memcached, etc. is not what we want.
I've researched the topic somewhat and found that there are some possible alternatives like:
Tayzgrid - Last update seems to be quite some time ago, not sure if still actively maintained
Druid - Still incubating, and I have also read that new releases being somewhat broken was not that uncommon
Hazelcast - Seems like the best choice given its maturity and the existence of Spring Data Hazelcast, though I am unsure what the level of support is here.
Has anyone has experience with integrating one of the above IMDGs (aside from Ignite) with Spring Cache? Any pointers in the right direction would be greatly appreciated.
You can use Redisson - Redis Java client with features of
In-Memory Data Grid. It also implements Spring Data support. Here is the documentation.
Hazelcast has official support for Spring Data Hazelcast and also this module has many users as now. I can also suggest you to have a look at the resources below:
Using Hazelcast with Spring Data
Getting Started with Microservices Using Hazelcast IMDG and Spring Boot
I am new to Spring cache abstraction. I have explored it using ehcache and apache ignite caching providers.
I want to know if spring cache abstraction supports the caching strategies of Write-behind and write-through.
Thanks,
bs
There is no direct support for cache-through in the declarative Spring abstraction.
And in a way it makes sense, since the abstraction lets you surround methods with caching related annotations. But with a cache-through pattern, the whole method would only be a cache interaction: a get for read, or a put for write. Not the if-then-else that the annotation abstracts.
However, if you use the CacheManager and Cache interfaces provided by Spring directly in your code, you can perfectly use them in a cache-through way.
Ignite cache has a notion of CacheStore interface that used in cases when there is a need to wire the cache with a persistent store (RDBMS, MongoDB, Hadoop, etc.). This interface provides write-through/write-behind and read-through semantics. Please refer to this documentation for more details.
Also I would recommend taking look at various examples that demonstrates how particular CacheStore implementations are used in Ignite. The examples are available in Ignite release bundles.
I am afraid I have got some pretty basic questions about ehcache. I would like to use caching mechanism on clustered Glassfish without any significant infrastrucure.
As I know using ditributed cache with ehcache means that I have to use the terracotta server array, don't?
I am not so experienced in caching so could I use the ehcache on clustered glassfish that I just put some JAR into the classpath of Glassfish or deploy a WAR or something onto Glassfish and that's it? Do I have to use an external cache server anyway?
The replicated cache in ehcache doesn't need the terracotta server array, do it?
I would like to store a java Map object in the store which is going to be changed quite often. In this case the replicated cache is not best choice, as I know. The Hazelcast distributed cache needs any external cache server?
Thank you very much for your help in advance!
Have a nice day, experts!
Hazelcast doesn't need any externel server if you are running Java.
Basically add hazelcast.jar into your classpath. And from your application creata an Hazelcast instance:
HazelcastInstance hazelcast = Hazelcast.newHazelcastInstance(new Config());
then to get a distributed map:
Map map = hazelcast.getMap("myMap");
that's it. In this example I provided the default config which uses Multicast to discovery of the nodes. You can update and change any parameter.
For more information see Quick Start Tutorial
The replication feature in Ehcache does not require any server. You simply add the Ehcache jar to your web application and configure Ehcache to replicate to all cluster nodes. You can choose whether to automatically discover all GlassFish nodes using multicast or you can manually tell Ehcache where to find the other nodes. You can find the Ehcache replication configuration instructions here: http://ehcache.org/documentation/replication/rmi-replicated-caching#configuring-the-peer-provider
Hazelcast works similarly. See here for documentation: http://hazelcast.org/docs/3.0/manual/html/ch12s02.html
Hi I have one Grails application, it uses Spring cache. I want to clone it (say APP_A and APP_B) and deploy on separate it as each access different DB and has some different configuration.
Currently I have two copy of Jetty servers (JETTY_A, JETTY_B. different port). I put APP_A in Jetty_A and APP_B in Jetty_B.
I'm not familiar with Spring cache.
Is this deployment save? I mean, will there be any mix of cache between both? Because both using the same code base. So, the cache will use the same key name.
#cacheable("someCache")
SpringCache uses EHCache under the covers. The caches are in-process caches and they do not affect caches running in other processes on the same machine, unless you had explicitly configured distributed caching.
As #KenLiu said in his answer, Spring Cache is strictly in-process when using EHCache as it's cache provider. Since you are working with Grails, however, there are better alternatives that will require only minimal changes.
The Grails Cache Plugin is a offers a Spring Cache API-compatible cache abstraction over a number of (plugable) cache providers, including some, like the Redis provider, that allow you to cache between processes (and entire machines) very easily.
Spring provides a useful feature of Cache Abstraction
But what I could not find is a provider agnostic way to get live cache statistics. Essentially I just want to show a list of all the cache names and their corresponding keys with the count of hits, misses, and sizes (in kb) either on a web page or via JMX. I know Ehcache does provide this feature and if I use ehcache API inside the code I can get it (have already used it in the past). But I believe using Ehcache API inside the code takes away the whole notion of the Spring framework's cache abstraction.
The only common, provider-agnostic thing you have is CacheManager interface, which provides the following method:
Collection<String> getCacheNames()
It returns a collection of the caches known by the cache manager.