How to write GC log to named pipe in Java 9?

Question

Before Java9, we can just specify -Xloggc:/my/named/pipe to log garbage collection messages into a named pipe. However, when specifying -Xlog:gc*:file=/my/named/pipe, JVM 9 complains about the named pipe:

[0.003s][error][logging] Unable to log to file /my/named/pipe,  /my/named/pipe is not a regular file.

We are using Linux RedHat with jdk_9.0.1_x64.

How can we log GC messages to a named pipe in Java 9?

Answer 1

Looking at the syntax specified under Unified JVM Logging, could you try replacing the arg from

-xlog:gc*.file=/my/named/pip

to

-Xlog:gc*=info:file=gctrace.txt
           ^  ^          ^
       level  colon   filename

or simply

-Xlog:gc*:file=gctrace.txt // since default level for gc logging is INFO