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1*c29d5175SchristosJava - DTracing Java
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3*c29d5175Schristos   These scripts trace the JVM, and require the Java hotspot provider which
4*c29d5175Schristos   was shipped with Java starting with version 1.6.0.
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6*c29d5175Schristos   Some of these scripts measure method and object events, and require
7*c29d5175Schristos   the Java process to be run using the "+ExtendedDTraceProbes" flag.
8*c29d5175Schristos   For example,
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10*c29d5175Schristos	java -XX:+ExtendedDTraceProbes classfile
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12*c29d5175Schristos   The ExtendedDTraceProbes flag is not on by default to avoid the additional
13*c29d5175Schristos   overhead for maintaining these additional probes. When this flag is
14*c29d5175Schristos   enabled, the JVM may execute slightly slower than before; when the probes
15*c29d5175Schristos   are also enabled (especially method probes), the JVM may execute
16*c29d5175Schristos   significantly slower.
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