Ratnakar Malla

Generalist - Security & Performance Architect

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Installing Hue on HDP 2.1

When installing Hue on Hadoop Data Platform from Horton Works, you might run into issue compiling the code.
Maven fails with the following stack trace:

cd hue-3.8.1/desktop/libs/hadoop/java && mvn clean install -DskipTests

Jul 13, 2015 10:49:26 p.m. com.google.inject.internal.MessageProcessor visit

INFO: An exception was caught and reported. Message: java.util.NoSuchElementException

java.util.NoSuchElementException

at java.util.AbstractList$1.next(libgcj.so.10)

at com.google.inject.spi.InjectionPoint.forMember(InjectionPoint.java:116)

at com.google.inject.spi.InjectionPoint.(InjectionPoint.java:73)

at com.google.inject.spi.InjectionPoint$InjectableMethod.toInjectionPoint(InjectionPoint.java:459)

at com.google.inject.spi.InjectionPoint.getInjectionPoints(InjectionPoint.java:725)

at com.google.inject.spi.InjectionPoint.forInstanceMethodsAndFields(InjectionPoint.java:358)

at

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Solving performance problems on Java web applications - Our experiences

This material is from my presentation at Silicon Valley Code Camp - 2014
svcc-2014-presentation.PNG

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Trouble with EhCache

We are running EhCache in production, and the cache has been configured with Cache size in memory and on the disk.
However, upon analysis of heap dump using Eclipse Memory Analysis Tool (MAT), we noticed the EhCache was using almost 80% of the memory.

Heap Snapshot

Further research of EhCache , and reading forums, we noticed that the open source version of EhCache was a crippleware, with a serious limitation.
Here is what I read from EhCache forums:

*As you have noticed the open-source disk stores do not store the entire cache on disk. Instead the values are stored on the disk, and the keys are stored in memory mapped to value objects which reference where on disk the associated value object can be found. This means each on-disk mapping has an associated in-memory overhead equal to it’s key-size plus a fixed overhead per mapping. *

Ref: EhCache Forum Post

In conclusion it is very important

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