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Java Flight Recorder

The Java Flight Recorder (JFR) translator is responsible to decompress a JFR recording file.

A default JFR translator configuration is provided in standard.
It is available in the analyzer/config/translators/jfr of your Jeyzer installation.

The translator will take a JFR recording file (prefixed with .jfr) and convert (“uncompress”) the JFR events it contains into JZR snapshots.
Once uncompressed, those will be processed by the other Jeyzer translators, such as the de-obfuscation one.

The jfr_uncompress.xml defines the JFR analysis Jeyzer settings. Duplicate it if required for customization needs.

Decompressed files get stored in the jfr_uncompressed directory and are by default not kept at the end of the analysis.
Set the keep_files option to true to keep it.

For control purposes, the JFR events can be dump into distinct text files (per_type) and/or globally (all) through the dump_events settings.
Files get generated in the jfr_dump directory by default.
The list of event types is also printed in the eventTypes-jfr.txt file.

Decompression limits are set to protect against invasive JFR files.
The file_size_limit is the maximum JFR file size in Mb which can be accepted. If not specified, default value is 100Mb.
This limit is particularly important in a web context. The Jeyzer Web Analyzer relies on it : its configuration is then set at the web level.

<translator>

  <jfr_uncompress keep_files="false" directory="${JEYZER_RECORD_DIRECTORY}/jfr_uncompressed">

    <dump_events per_type="false" all="false" directory="${JEYZER_RECORD_DIRECTORY}/jfr_dump"/>

    <limits file_size_limit="${JEYZER_TRANSLATOR_FILE_MAX_SIZE}"/>

  </jfr_uncompress>

</translator>