db.currentOp() - MongoDB in-progress operations for database instance

db.currentOp() will return a document that reports in-progress operations for the database instance


i.e

db.currentOp(true)
This will return a more descriptive output, including idle connections and system operations.

Note: db.currentOp() is available only for Administrative users




To get current users;

db.currentOp().inprog.forEach(
   function(d){
     if(d.client)
        printjson(d.client)
     })

 Shards Environment

db.currentOp().inprog.forEach(

   function(d){

     if(d.client_s)

        printjson(d.client_s)

     })

Return the active write operation 

db.currentOp().inprog.forEach(

   function(d){

     if(d.active && d.lockType == "write")

        printjson(d)

     })

Return all active read operations

db.currentOp().inprog.forEach(

   function(d){

     if(d.active && d.lockType == "read")

        printjson(d)

     })

Source Link :   http://docs.mongodb.org/manual/reference/method/db.currentOp/

MongoDB Profiler

MongoDB Profiler

database profiler is the process of examining the data available in  existing database(s) and collecting statistics information about the database related action.

Link: http://docs.mongodb.org/manual/tutorial/manage-the-database-profiler/

Profiling Stages,

You can retrieve  update , remove and select queries but you will not be able to get more details about insert queries

The following profiling levels are available:
Level Setting
0       Off. No profiling
1       Only includes “slow” operations ( default 100ms)
2       Includes all operations


This link will tell you profiler out put result details

http://docs.mongodb.org/manual/reference/database-profiler/

Here is the deal

How we can get latest or all operation query details from system.profiler collection

As an example,i'm using "test" database and "sample"

Limit(number) will limit your out put result. if you wan to get all out put remove ".limit()" function from the command.

Enable Profiler on test database

1) check existing profiler status
db.getProfilingLevel()
      You will get 0,1 or 2

2) set profiling for all operations
db.setProfilingLevel(2)
      { "was" : 0, "slowms" : 100, "ok" : 1 }

3) check ur profiling state again,
db.getProfilingLevel()

Now I'm inserting data.

use test
db.sample.insert({_id:1 ,"text":"Sample Text"})


Here is there record in system.profile collection related to latest insert operation

     db.system.profile.find({"op":"insert"}).sort({ts:-1}).limit(1).pretty()

{
        "op" : "insert",
        "ns" : "test.sample",
        "ninserted" : 1,
        "keyUpdates" : 0,
        "numYield" : 0,
        "lockStats" : {
                "timeLockedMicros" : {
                        "r" : NumberLong(0),
                        "w" : NumberLong(1283230)
                },
                "timeAcquiringMicros" : {
                        "r" : NumberLong(0),
                        "w" : NumberLong(94889)
                }
        },
        "millis" : 1291,
        "ts" : ISODate("2014-07-15T05:19:57.958Z"),
        "client" : "127.0.0.1",
        "allUsers" : [ ],
        "user" : ""
}



Now updating

db.sample.update({_id:1},{"Text":"Sample Text New"})

This what captured in system.profile collection

{
        "op" : "update",
        "ns" : "test.sample",
        "query" : {
                "_id" : 1
        },
        "updateobj" : {
                "Text" : "Sample Text New"
        },
        "idhack" : true,
        "moved" : true,
        "nmoved" : 1,
        "nupdated" : 1,
        "keyUpdates" : 0,
        "numYield" : 0,
        "lockStats" : {
                "timeLockedMicros" : {
                        "r" : NumberLong(0),
                        "w" : NumberLong(28005)
                },
                "timeAcquiringMicros" : {
                        "r" : NumberLong(0),
                        "w" : NumberLong(19)
                }
        },
        "millis" : 28,
        "ts" : ISODate("2014-07-15T05:57:32.157Z"),
        "client" : "127.0.0.1",
        "allUsers" : [ ],
        "user" : ""
}


Remove document

db.sample.remove({_id:2})

db.system.profile.find({"op":"remove"}).sort({ts:-1}).limit(1).pretty()

{
        "op" : "remove",
        "ns" : "test.sample",
        "query" : {
                "_id" : 2
        },
        "ndeleted" : 1,
        "keyUpdates" : 0,
        "numYield" : 1,
        "lockStats" : {
                "timeLockedMicros" : {
                        "r" : NumberLong(0),
                        "w" : NumberLong(85442)
                },
                "timeAcquiringMicros" : {
                        "r" : NumberLong(0),
                        "w" : NumberLong(43545)
                }
        },
        "millis" : 43,
        "ts" : ISODate("2014-07-15T06:35:24.784Z"),
        "client" : "127.0.0.1",
        "allUsers" : [ ],
        "user" : ""
}


Query collection

db.sample.find({_id:1})

db.system.profile.find({"op":"query"}).sort({ts:-2}).limit(1).pretty()

{
        "op" : "query",
        "ns" : "test.system.profile",
        "query" : {
                "query" : {
                        "op" : "query"
                },
                "orderby" : {
                        "ts" : -2
                }
        },
        "ntoreturn" : 1,
        "ntoskip" : 0,
        "nscanned" : 114,
        "scanAndOrder" : true,
        "keyUpdates" : 0,
        "numYield" : 0,
        "lockStats" : {
                "timeLockedMicros" : {
                        "r" : NumberLong(931),
                        "w" : NumberLong(0)
                },
                "timeAcquiringMicros" : {
                        "r" : NumberLong(7),
                        "w" : NumberLong(6)
                }
        },
        "nreturned" : 1,
        "responseLength" : 400,
        "millis" : 0,
        "ts" : ISODate("2014-07-15T06:53:58.221Z"),
        "client" : "127.0.0.1",
        "allUsers" : [ ],
        "user" : ""
}