Task Resource

The Task resource provides a set of REST endpoints that give openLooKeng servers the ability to communicate about tasks and task output. This isn’t a service that will be used by end users, but it supports the execution of queries on a openLooKeng installation.

  • GET /v1/task

Returns information about all tasks known to a openLooKengServer.

Note that the output of a call to /v1/task can be quite large. If you execute this against a busy openLooKeng server the response received will include a listing of every task known to that server along with detailed statistics about operators and drivers.

The following example response shows a trivial task response that has been truncated to fit this manual. A real response from a busy openLooKeng server would generate pages and pages of output. Here there is a taskId for a task which is in the CANCELED state.

Example response:

  1. [ {
  2.   "taskId" : "20131222_183944_00011_dk5x2.1.0",
  3.   "version" : 9223372036854775807,
  4.   "state" : "CANCELED",
  5.   "self" : "unknown",
  6.   "lastHeartbeat" : "2013-12-22T13:54:46.566-05:00",
  7.   "outputBuffers" : {
  8.     "state" : "FINISHED",
  9.     "masterSequenceId" : 0,
  10.     "pagesAdded" : 0,
  11.     "buffers" : [ ]
  12.   },
  13.   "noMoreSplits" : [ ],
  14.   "stats" : {
  15.     "createTime" : "2013-12-22T13:54:46.566-05:00",
  16.     "elapsedTime" : "0.00ns",
  17.     "queuedTime" : "92.00us",
  18.     "totalDrivers" : 0,
  19.     "queuedDrivers" : 0,
  20.     "runningDrivers" : 0,
  21.     "completedDrivers" : 0,
  22.     "memoryReservation" : "0B",
  23.     "totalScheduledTime" : "0.00ns",
  24.     "totalCpuTime" : "0.00ns",
  25.     "totalBlockedTime" : "0.00ns",
  26.     "rawInputDataSize" : "0B",
  27.     "rawInputPositions" : 0,
  28.     "processedInputDataSize" : "0B",
  29.     "processedInputPositions" : 0,
  30.     "outputDataSize" : "0B",
  31.     "outputPositions" : 0,
  32.     "pipelines" : [ ]
  33.   },
  34.   "failures" : [ ],
  35.   "outputs" : { }
  36. }]

  • POST /v1/task/{taskId}

  • DELETE /v1/task/{taskId}

Deletes a given task from a openLooKeng server.

  • GET /v1/task/{taskId}

Retrieves information about a specific task by taskId.

The following example lists the output of a task. It contains the following high-level sections:

  • outputBuffers
  • noMoreSplits
  • stats
  • failures
  • outputs

This is the same output that is also present in the response from the Query resource which lists all of the stages and tasks involved in a particular query. This is call is used by openLooKeng to coordinate a queries.

Example response:

  1. {
  2. "taskId" : "20140115_170528_00004_dk5x2.0.0",
  3. "version" : 42,
  4. "state" : "FINISHED",
  5. "self" : "http://10.193.207.128:8080/v1/task/20140115_170528_00004_dk5x2.0.0",
  6. "lastHeartbeat" : "2014-01-15T12:12:12.518-05:00",
  7. "outputBuffers" : {
  8. "state" : "FINISHED",
  9. "masterSequenceId" : 0,
  10. "pagesAdded" : 1,
  11. "buffers" : [ {
  12.   "bufferId" : "out",
  13.   "finished" : true,
  14.   "bufferedPages" : 0,
  15.   "pagesSent" : 1
  16. } ]
  17. },
  18. "noMoreSplits" : [ "8" ],
  19. "stats" : {
  20. "createTime" : "2014-01-15T12:12:08.520-05:00",
  21. "startTime" : "2014-01-15T12:12:08.526-05:00",
  22. "endTime" : "2014-01-15T12:12:12.518-05:00",
  23. "elapsedTime" : "4.00s",
  24. "queuedTime" : "6.39ms",
  25. "totalDrivers" : 1,
  26. "queuedDrivers" : 0,
  27. "runningDrivers" : 0,
  28. "completedDrivers" : 1,
  29. "memoryReservation" : "174.76kB",
  30. "totalScheduledTime" : "4.19ms",
  31. "totalCpuTime" : "4.09ms",
  32. "totalBlockedTime" : "29.50ms",
  33. "rawInputDataSize" : "10.90kB",
  34. "rawInputPositions" : 154,
  35. "processedInputDataSize" : "10.90kB",
  36. "processedInputPositions" : 154,
  37. "outputDataSize" : "10.90kB",
  38. "outputPositions" : 154,
  39. "pipelines" : [ {
  40.   "inputPipeline" : true,
  41.   "outputPipeline" : true,
  42.   "totalDrivers" : 1,
  43.   "queuedDrivers" : 0,
  44.   "runningDrivers" : 0,
  45.   "completedDrivers" : 1,
  46.   "memoryReservation" : "0B",
  47.   "queuedTime" : {
  48.     "maxError" : 0.0,
  49.     "count" : 1.0,
  50.     "total" : 5857000.0,
  51.     "p01" : 5857000,
  52.     "p05" : 5857000,
  53.     "p10" : 5857000,
  54.     "p25" : 5857000,
  55.     "p50" : 5857000,
  56.     "p75" : 5857000,
  57.     "p90" : 5857000,
  58.     "p95" : 5857000,
  59.     "p99" : 5857000,
  60.     "min" : 5857000,
  61.     "max" : 5857000
  62.   },
  63.   "elapsedTime" : {
  64.     "maxError" : 0.0,
  65.     "count" : 1.0,
  66.     "total" : 4.1812E7,
  67.     "p01" : 41812000,
  68.     "p05" : 41812000,
  69.     "p10" : 41812000,
  70.     "p25" : 41812000,
  71.     "p50" : 41812000,
  72.     "p75" : 41812000,
  73.     "p90" : 41812000,
  74.     "p95" : 41812000,
  75.     "p99" : 41812000,
  76.     "min" : 41812000,
  77.     "max" : 41812000
  78.   },
  79.   "totalScheduledTime" : "4.19ms",
  80.   "totalCpuTime" : "4.09ms",
  81.   "totalBlockedTime" : "29.50ms",
  82.   "rawInputDataSize" : "10.90kB",
  83.   "rawInputPositions" : 154,
  84.   "processedInputDataSize" : "10.90kB",
  85.   "processedInputPositions" : 154,
  86.   "outputDataSize" : "10.90kB",
  87.   "outputPositions" : 154,
  88.   "operatorSummaries" : [ {
  89.     "operatorId" : 0,
  90.     "operatorType" : "ExchangeOperator",
  91.     "addInputCalls" : 0,
  92.     "addInputWall" : "0.00ns",
  93.     "addInputCpu" : "0.00ns",
  94.     "addInputUser" : "0.00ns",
  95.     "inputDataSize" : "10.90kB",
  96.     "inputPositions" : 154,
  97.     "getOutputCalls" : 1,
  98.     "getOutputWall" : "146.00us",
  99.     "getOutputCpu" : "137.90us",
  100.     "getOutputUser" : "0.00ns",
  101.     "outputDataSize" : "10.90kB",
  102.     "outputPositions" : 154,
  103.     "blockedWall" : "29.50ms",
  104.     "finishCalls" : 0,
  105.     "finishWall" : "0.00ns",
  106.     "finishCpu" : "0.00ns",
  107.     "finishUser" : "0.00ns",
  108.     "memoryReservation" : "0B",
  109.     "info" : {
  110.   "bufferedBytes" : 0,
  111.   "averageBytesPerRequest" : 11158,
  112.   "bufferedPages" : 0,
  113.   "pageBufferClientStatuses" : [ {
  114.     "uri" : "http://10.193.207.128:8080/v1/task/20140115_170528_00004_dk5x2.1.0/results/ab68e201-3878-4b21-b6b9-f6658ddc408b",
  115.     "state" : "closed",
  116.     "lastUpdate" : "2014-01-15T12:12:08.562-05:00",
  117.     "pagesReceived" : 1,
  118.     "requestsScheduled" : 3,
  119.     "requestsCompleted" : 3,
  120.     "httpRequestState" : "queued"
  121.   } ]
  122.     }
  123.   }, {
  124.     "operatorId" : 1,
  125.     "operatorType" : "FilterAndProjectOperator",
  126.     "addInputCalls" : 1,
  127.     "addInputWall" : "919.00us",
  128.     "addInputCpu" : "919.38us",
  129.     "addInputUser" : "0.00ns",
  130.     "inputDataSize" : "10.90kB",
  131.     "inputPositions" : 154,
  132.     "getOutputCalls" : 2,
  133.     "getOutputWall" : "128.00us",
  134.     "getOutputCpu" : "128.64us",
  135.     "getOutputUser" : "0.00ns",
  136.     "outputDataSize" : "10.45kB",
  137.     "outputPositions" : 154,
  138.     "blockedWall" : "0.00ns",
  139.     "finishCalls" : 5,
  140.     "finishWall" : "258.00us",
  141.     "finishCpu" : "253.19us",
  142.     "finishUser" : "0.00ns",
  143.     "memoryReservation" : "0B"
  144.   }, {
  145.     "operatorId" : 2,
  146.     "operatorType" : "OrderByOperator",
  147.     "addInputCalls" : 1,
  148.     "addInputWall" : "438.00us",
  149.     "addInputCpu" : "439.18us",
  150.     "addInputUser" : "0.00ns",
  151.     "inputDataSize" : "10.45kB",
  152.     "inputPositions" : 154,
  153.     "getOutputCalls" : 4,
  154.     "getOutputWall" : "869.00us",
  155.     "getOutputCpu" : "831.85us",
  156.     "getOutputUser" : "0.00ns",
  157.     "outputDataSize" : "10.45kB",
  158.     "outputPositions" : 154,
  159.     "blockedWall" : "0.00ns",
  160.     "finishCalls" : 4,
  161.     "finishWall" : "808.00us",
  162.     "finishCpu" : "810.18us",
  163.     "finishUser" : "0.00ns",
  164.     "memoryReservation" : "174.76kB"
  165.   }, {
  166.     "operatorId" : 3,
  167.     "operatorType" : "FilterAndProjectOperator",
  168.     "addInputCalls" : 1,
  169.     "addInputWall" : "166.00us",
  170.     "addInputCpu" : "166.66us",
  171.     "addInputUser" : "0.00ns",
  172.     "inputDataSize" : "10.45kB",
  173.     "inputPositions" : 154,
  174.     "getOutputCalls" : 5,
  175.     "getOutputWall" : "305.00us",
  176.     "getOutputCpu" : "241.14us",
  177.     "getOutputUser" : "0.00ns",
  178.     "outputDataSize" : "10.90kB",
  179.     "outputPositions" : 154,
  180.     "blockedWall" : "0.00ns",
  181.     "finishCalls" : 2,
  182.     "finishWall" : "70.00us",
  183.     "finishCpu" : "71.02us",
  184.     "finishUser" : "0.00ns",
  185.     "memoryReservation" : "0B"
  186.   }, {
  187.     "operatorId" : 4,
  188.     "operatorType" : "TaskOutputOperator",
  189.     "addInputCalls" : 1,
  190.     "addInputWall" : "50.00us",
  191.     "addInputCpu" : "51.03us",
  192.     "addInputUser" : "0.00ns",
  193.     "inputDataSize" : "10.90kB",
  194.     "inputPositions" : 154,
  195.     "getOutputCalls" : 0,
  196.     "getOutputWall" : "0.00ns",
  197.     "getOutputCpu" : "0.00ns",
  198.     "getOutputUser" : "0.00ns",
  199.     "outputDataSize" : "10.90kB",
  200.     "outputPositions" : 154,
  201.     "blockedWall" : "0.00ns",
  202.     "finishCalls" : 1,
  203.     "finishWall" : "35.00us",
  204.     "finishCpu" : "35.39us",
  205.     "finishUser" : "0.00ns",
  206.     "memoryReservation" : "0B"
  207.   } ],
  208.   "drivers" : [ ]
  209. } ]
  210. },
  211. "failures" : [ ],
  212. "outputs" : { }
  213. }
  • GET /v1/task/{taskId}/results/{outputId}/{token}

This service is used by openLooKeng to retrieve task output.

  • DELETE /v1/task/{taskId}/results/{outputId}

This service is used by openLooKeng to delete task output.