HOWTO: Extract performance data directly from the Metric Store

As discussed elsewhere, the metrics collected by CBTOOL can be grouped in three categories: Management performance metrics (management), Application performance metrics (runtime_app), and OS resource usage metrics (runtime_os). Unsurprisingly the data is stored in the Metric Store (a MongoDB data store) in collections whose names contain the management, runtime_app or runtime_os string.

The data structure of the Metric Store is the following:

> show dbs

local (empty)
metrics 5.951171875GB
test (empty)

> use metrics

switched to db metrics

> show collections

latest_management_VM_msilva
latest_runtime_os_HOST_msilva
management_HOST_msilva
management_VM_msilva
reported_management_VM_metric_names_msilva
reported_runtime_app_VM_metric_names_msilva
reported_runtime_os_HOST_metric_names_msilva
reported_runtime_os_VM_metric_names_msilva
runtime_app_VM_msilva
runtime_os_HOST_msilva
runtime_os_VM_msilva
system.indexes
trace_msilva```

Please note that the name formation rule for each collection is PREFIXCATEGORYOBJECT_USERNAME. collection category (i.e., management, runtime_app or runtime_os) is prefixed by either reported, latest or nothing. The reported and latest are used only by the CloudBench GUI, and shouldn't be directly accessed by a CBTOOL user. The important collections, containing the actual data that can be extract and analyzed are then the ones that do not have a prefix. The usual naming formation rule for each collection is