Download - SeamCat

CEPT
ECC
Electronic Communications Committee
SEAMCAT Technical Group (STG)
Date issued:
20th July 2016
Source:
ECO
Subject:
SEAMCAT performance and 32 bit JRE issues
Type of report (Bug / Enhancement / New Feature)
For info
SEAMCAT version (e.g. 5.0.0)
5.0.1
SEAMCAT component involved
Main calculation
Background information, reference documents and related tickets
Previous memory issues that affected simulation performance.
Description of the issue (please include workspaces, screenshots, log files, etc.)
Tests have been carried out to benchmark the simulation time of SEAMCAT on machines with
different specifications, including high performance server machines.
During the course of this testing, it was found that significant performance issues can arise if
running the 32 bit variant of the Java Runtime Environment (JRE). This can be resolved easily by
separately installing the 64 bit JRE variant. It is necessary to manually install it, as attempting to
update Java will only update to the latest 32 bit version. Both variants can be installed separately
(and it should be noted that the 32 bit variant is required for SEAMCAT v4 and older).
Use of the 64 bit JRE means that SEAMCAT can access all the memory it needs, and therefore the
previous recommendations provided on the website to specify maximum memory of 1024 MB no
longer apply, and will in fact limit performance on most installations.
The tests additionally show that significant performance improvements can be made if using high
performance machines. Provided that the 64-bit JRE is used, SEAMCAT can make full use of
memory and can efficiently use parallel processing on multiple cores.
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The full performance test results are provided in Annex 1 to this document.
Proposal
To modify the existing Installation Instructions point 2 on www.seamcat.org as follows:
2. Once registered the download can proceed. It consists of a single file (.jar file) which can
be launched by running it with the Java launcher. NOTE : to ensure optimum performance
on 64-bit operating systems please ensure you
have the 64-bit variant of the Java
Runtime Environment installed.
To modify System Requirements point 1 as follows :
1. Make sure you have the Java Runtime Environment version 7 and above. You can test your
Java version here. NOTE : if you are running on a 64 bit OS (most modern systems) please
ensure you have the 64 bit variant of the JRE installed. It can be downloaded here.
High
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