Author: Buczak, W.
Paper Title Page
FRBHMUST02 Towards High Performance Processing in Modern Java Based Control Systems 1322
 
  • M. Misiowiec, W. Buczak, M. Buttner
    CERN, Geneva, Switzerland
 
  CERN controls software is often developed on Java foundation. Some systems carry out a combination of data, network and processor intensive tasks within strict time limits. Hence, there is a demand for high performing, quasi real time solutions. Extensive prototyping of the new CERN monitoring and alarm software required us to address such expectations. The system must handle dozens of thousands of data samples every second, along its three tiers, applying complex computations throughout. To accomplish the goal, a deep understanding of multithreading, memory management and interprocess communication was required. There are unexpected traps hidden behind an excessive use of 64 bit memory or severe impact on the processing flow of modern garbage collectors, including the state of the art Oracle GarbageFirst. Tuning JVM configuration significantly affects the execution of the code. Even more important is the amount of threads and the data structures used between them. Accurately dividing work into independent tasks might boost system performance. Thorough profiling with dedicated tools helped understand the bottlenecks and choose algorithmically optimal solutions. Different virtual machines were tested, in a variety of setups and garbage collection options. The overall work provided for discovering actual hard limits of the whole setup. We present this process of architecting a challenging system in view of the characteristics and limitations of the contemporary Java runtime environment.
http://cern.ch/marekm/icalepcs.html
 
slides icon Slides FRBHMUST02 [4.514 MB]