trackrdrd: added docs about logging and monitoring

datalog.rst

+================== ============================================================
+Field              Description
+================== ============================================================
+``len``            Size of the data table
+                   (``maxdone`` + 2\ :sup:``maxopen.scale``\)
+------------------ ------------------------------------------------------------
+``nodata``         Number of request records that contained no data (nothing to
+                   track in a ``VCL_log`` entry). These records are discarded
+                   without sending a message to a message broker.
+------------------ ------------------------------------------------------------
+``submitted``      Number of records passed from the reader thread to worker
+                   threads to be sent to a message broker
+------------------ ------------------------------------------------------------
+``wait_room``      How often the reader thread had to wait for space in the
+                   data table
+------------------ ------------------------------------------------------------
+``data_hi``        Data high watermark -- longest record since startup (in
+                   bytes)
+------------------ ------------------------------------------------------------
+``data_overflows`` How often the accumulated length of a record exceeded
+                   ``maxdata``
+------------------ ------------------------------------------------------------
+``done``           Current number of records in state "done"
+------------------ ------------------------------------------------------------
+``open``           Current number of open records in the table
+------------------ ------------------------------------------------------------
+``load``           Current number records in the table as percent
+                   (100 * (``open`` + ``done``)/``len``)
+------------------ ------------------------------------------------------------
+``sent``           Number of records successfully sent to a message broker
+------------------ ------------------------------------------------------------
+``reconnects``     How often worker threads reconnected to a message broker
+                   after an unsuccessful send
+------------------ ------------------------------------------------------------
+``failed``         Number of failed sends (failure after reconnect)
+------------------ ------------------------------------------------------------
+``occ_hi``         Occupancy high watermark -- highest number of records (open
+                   and done) since startup
+------------------ ------------------------------------------------------------
+``occ_hi_this``    Occupancy high watermark in the current monitoring interval
+================== ============================================================
+

hashlog.rst

+================= =============================================================
+Field             Description
+================= =============================================================
+``len``           Size of the hash table (2\ :sup:``maxopen.scale``\)
+----------------- -------------------------------------------------------------
+``seen``          Number of request records read (``ReqStart`` seen)
+----------------- -------------------------------------------------------------
+``drop_reqstart`` Number of records that could not be inserted into internal
+                  tables (no data from ``ReqStart`` inserted, nor any other
+                  data for that XID)
+----------------- -------------------------------------------------------------
+``drop_vcl_log``  How often data from ``VCL_log`` could not be inserted
+                  (usually because the XID could not be found)
+----------------- -------------------------------------------------------------
+``drop_reqend``   How often data from ``ReqStart`` could not be inserted
+                  (usually because the XID could not be found)
+----------------- -------------------------------------------------------------
+``expired``       Number of records for which ``hash.ttl`` expired (data sent
+                  to message broker without waiting for ``ReqEnd``)
+----------------- -------------------------------------------------------------
+``evacuated``     Number of records removed to recover space in the hash table
+                  (``hash.mlt`` expired, data possibly incomplete)
+----------------- -------------------------------------------------------------
+``open``          Current number of open records in the table
+----------------- -------------------------------------------------------------
+``load``          Current open records as percent (``open``/``len`` * 100)
+----------------- -------------------------------------------------------------
+``collisions``    Number of hash collisions
+----------------- -------------------------------------------------------------
+``insert_probes`` Number of hash insert probes
+----------------- -------------------------------------------------------------
+``find_probes``   Number of hash find probes
+----------------- -------------------------------------------------------------
+``fail``          Number of failed hash operations (insert or find)
+----------------- -------------------------------------------------------------
+``occ_hi``        Occupancy high watermark -- highest number of open records
+                  since startup
+----------------- -------------------------------------------------------------
+``occ_hi_this``   Occupancy high watermark in the current monitoring interval
+================= =============================================================
+