[jira] [Created] (IGNITE-8726) Highlight that memory metrics are local for a node in the docs

["Stanislav Lukyanov (JIRA)" <ji...@apache.org>]

Stanislav Lukyanov created IGNITE-8726:
------------------------------------------

             Summary: Highlight that memory metrics are local for a node in the docs
                 Key: IGNITE-8726
                 URL: https://issues.apache.org/jira/browse/IGNITE-8726
             Project: Ignite
          Issue Type: Improvement
          Components: documentation
            Reporter: Stanislav Lukyanov


Memory Metrics (DataRegionMetrics and DataStorageMetrics) in Ignite are local for each node. However, this is not highlighted in the documentation enough. The code snippets suggest to just call `ignite.dataRegionMetrics()` which seems to be a bit at odds with the general use case of Ignite servers being started via ignite.sh.

It would be good to have an easily noticeable warning that the metrics will only return data for the local node (and that, for example, on client they would typically always print 0).

Also, would be nice to include a couple of practical approaches other than JMX to collect metrics. E.g. a snippet of client code getting metrics from all servers:
{code}
Collection<String> metricsFromNodes = ignite.compute().broadcast(() -> {
    Ignite ignite = Ignition.localIgnite();
    
    StringBuilder sb = new StringBuilder();
    
    sb.append("Node: " + ignite.name());
    
    for (DataRegionMetrics metrics : ignite.dataRegionMetrics()) {
        // append metrics to the builder 
    }
    
    return sb.toString();
});

for (String metricsString : metricsFromNodes)
    System.out.println(metricsString);
{code}



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)