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Alain Rastoul commented on CASSANDRA-13103: ------------------------------------------- Thank you for the review, Stefan. I checked the codahale metrics registry and the append method who adds the dot has been added in mars 2013 : https://github.com/dropwizard/metrics/commit/0ae1fc0292fa2f7509ab7f237f6a752e316a0d86 so IMHO this patch should be useful for any recent codahale library version use. > incorrect jvm metric names > -------------------------- > > Key: CASSANDRA-13103 > URL: https://issues.apache.org/jira/browse/CASSANDRA-13103 > Project: Cassandra > Issue Type: Bug > Components: Observability > Reporter: Alain Rastoul > Assignee: Alain Rastoul > Priority: Minor > Labels: lhf > Fix For: 3.9, 3.x > > Attachments: Fix-incorrect-jvm-metric-names-CASSANDRA-13103.patch > > > Some jvm metrics have a double dot in name like: > jvm.memory..total.max , jvm.memory..total.init (etc). > it seems that an extra dot is added at the end of the name in > CassandraDaemon.java, around line 367 (in 3.0.10): > ... > // enable metrics provided by metrics-jvm.jar > CassandraMetricsRegistry.Metrics.register("jvm.buffers.", new > BufferPoolMetricSet(ManagementFactory.getPlatformMBeanServer())); > CassandraMetricsRegistry.Metrics.register("jvm.gc.", new > GarbageCollectorMetricSet()); > CassandraMetricsRegistry.Metrics.register("jvm.memory.", new > MemoryUsageGaugeSet()); > and also added in append method of MetricRegistry. > Call stack is: > MetricRegistry>>registerAll(String prefix, MetricSet metrics) > MetricRegistry>>static String name(String name, String... names) > MetricRegistry>>static void append(StringBuilder builder, String part) > and in append the dot is also added: > ... > if(builder.length() > 0) { > builder.append('.'); > } > builder.append(part); > ... > The codahale MetricRegistry class seems to have no recent modification of > name or append methods, so it look like a small bug. > May be the fix could be to simply not to add the final dot in the metric > name, ie "jvm.buffers" instead of "jvm.buffers." -- This message was sent by Atlassian JIRA (v6.3.15#6346)