Stats list

Mcrouter exposes numerous counters which include: number of requests sent, number of replies received, start time, average request duration, etc. These stats are exposed by stats commands and in stats file.

Here is an explanation of what most important stats mean:

##Basic stats

• version
  Version of mcrouter binary.
• commandargs
  Command line used to start mcrouter.
• time
  Current server time.
• child_pid
  Process id of mcrouter instance.
• parent_pid
  Process id of process that started mcrouter.

##Stats logged to file

• asynclog_requests
  Number of failed deletes written to spool file. More about spool file read here.

• closed_inactive_connections
  Number of connections closed due to inactivity. Once connection is not used for more than a minute, mcrouter will force-close it. The period of inactivity is configured with --reset-inactive-connection-interval command line option.

• cmd_[operation]
  Average number of received requests per second drilled down by operation.

• cmd_[operation]_count
  Total number of received requests drilled down by operation.

• cmd_[operation]_out_failover
  Average number of sent failover requests per second drilled down by operation.

• cmd_[operation]_out_shadow
  Number of sent shadow requests per second drilled down by operation.

• cmd_[operation]_out
  Average number of sent normal (non-shadow, non-failover) requests per second drilled down by operation.

• cmd_[operation]_out_all
  Total number of sent requests per second (failover + shadow + normal)

• cmd_[operation]_out_count
  Total number of sent requests per second drilled down by operation.

• config_age
  How long ago (in seconds) mcrouter has reconfigured.

• config_failures
  How many times mcrouter failed to reconfigure (if > 0 and growing, check the config is valid)

• config_last_attempt
  UNIX timestamp of last time mcrouter tried to reconfigure.

• config_last_success
  UNIX timestamp of last time mcrouter reconfigured successfully.

• dev_null_requests
  Number of requests sent to DevNullRoute

• duration_us
  Average time of processing a request (i.e. receiving request and sending a reply).

• fibers_allocated
  Number of fibers (lightweight threads) created by mcrouter.

• proxy_reqs_processing
  Requests mcrouter started routing but didn't receive a reply yet.

• proxy_reqs_waiting
  Requests queued up and not routed yet.

• result_[reply result]_count
  Total number of replies received drilled down by reply result.

• result_[reply result]_failover
  Average number of replies per second received for failover requests drilled down by result.

• result_[reply result]_shadow
  Average number of replies per second received for shadow requests drilled down by result.

• result_[reply result]
  Average number of replies per second received for normal requests drilled down by reply result.

• result_[reply result]_all
  Average number of replies per second received for requests drilled down by reply result.

• start_time
  UNIX timestamp of mcrouter startup time.

• uptime
  How long ago (in seconds) mcrouter has started.