RFR (L): 8046148: JEP 158 Unified JVM Logging

John Rose john.r.rose at oracle.com
Thu Sep 10 00:48:36 UTC 2015

On Sep 9, 2015, at 7:05 AM, Marcus Larsson <marcus.larsson at oracle.com> wrote:
> The UL framework only supports writing of complete log lines. Some of the existing code prints parts of its log lines in chunks directly to the tty, which means that such logging can be interleaved by other writes to the tty causing split lines. This code will have to be reworked during the migration to the UL framework so that only complete lines are logged. Once this is done, there should be no split lines in the log anymore, so in a sense the problem will be resolved with UL. :)

And, "in a sense", we can transmit existing XML-style logs by dissolving them into disconnected sequences of lines.  But we can all agree that it's a pretty weak "sense", since it makes the real logs difficult or impossible to reassemble.

Here's my take on the interesting relations between the new design of decorated lines and the existing need (in the compilation logs) for hierarchical markup.

https://bugs.openjdk.java.net/browse/JDK-8046148#comment-13568278 <https://bugs.openjdk.java.net/browse/JDK-8046148#comment-13568278>

However much we are charmed by the simplicity of decorated single lines, simply wishing it so will not turn them into an adequate carrier channel for the compilation logs, without some "stretch goal" work, in the direction of jumbo (multi-line) log entries.

— John

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