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  1. Core Server
  2. SERVER-12710

Map-Reduce reports incorrect stats in db.currentOp

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    • Type: Icon: Bug Bug
    • Resolution: Done
    • Priority: Icon: Major - P3 Major - P3
    • None
    • Affects Version/s: 2.4.9, 2.5.5
    • Component/s: MapReduce
    • Query Execution
    • ALL
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      >for(i=0;i<16000;i++) {db.test.insert({val:i})}
>var mapFunction1 = function() {
			sleep(1);
                       emit(1,this.val);
                   };

>var reduceFunction1 = function(id, val) {
                          return Array.sum(val);
                      };
>db.test.mapReduce(                      mapFunction1,                      reduceFunction1,                      { out: "map_reduce_example",query:{val:{$gt:1}} }                    ) //see db.currentOp() in another shell while this one is running
      Show
      > for (i=0;i<16000;i++) {db.test.insert({val:i})} > var mapFunction1 = function() { sleep(1); emit(1, this .val); }; > var reduceFunction1 = function(id, val) { return Array.sum(val); }; >db.test.mapReduce( mapFunction1, reduceFunction1, { out: "map_reduce_example" ,query:{val:{$gt:1}} } ) //see db.currentOp() in another shell while this one is running

      In db.currentOp() we support status output for MR jobs. However, if query filter is used, we output status incorrectly:

      > db.currentOp()
{
	"inprog" : [
		{
			"opid" : 16406,
			"active" : true,
			"secs_running" : 6,
			"op" : "query",
			"ns" : "test.test",
			"query" : {
				"mapreduce" : "test",
				"map" : function () { sleep(1);                        emit(1,this.val);                    },
				"reduce" : function (id, val) {
                          return Array.sum(val);
                      },
				"out" : "map_reduce_example",
				"query" : {
					"val" : {
						"$gt" : 1
					}
				}
			},
			"client" : "127.0.0.1:57129",
			"desc" : "conn7",
			"threadId" : "0x106a87000",
			"connectionId" : 7,
			"locks" : {
				"^" : "r",
				"^test" : "R"
			},
			"waitingForLock" : false,
			"msg" : "m/r: (1/3) emit phase M/R: (1/3) Emit Progress: 5173/1 517300%",
			"progress" : {
				"done" : 5173,
				"total" : 1
			},
			"numYields" : 57,
			"lockStats" : {
				"timeLockedMicros" : {
					"r" : NumberLong(13163605),
					"w" : NumberLong(1055)
				},
				"timeAcquiringMicros" : {
					"r" : NumberLong(6595364),
					"w" : NumberLong(7)
				}
			}
		}
	]
}

      We need to handle filtered jobs correctly and not output misleading percentages in db.currentOp(). (output in logs is fine)

            Assignee:
            backlog-query-execution [DO NOT USE] Backlog - Query Execution
            Reporter:
            alex.komyagin@mongodb.com Alexander Komyagin (Inactive)
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              Created:
              Updated:
              Resolved: