Add in progress operation metrics

[flaviostutz]

db.currentOp().inprog.length

SHOW LONG RUNNING

db.currentOp().inprog.forEach(
function(op) {
if(op.secs_running > 5) printjson(op);
}
)

SHOW CURRENT LOCKS

db.currentOp(
{
$and: [
{"waitingForLock" : true},
{"ns" : "edidatico.testes-estudantes"}
]
}
)

db.currentOp(
{
$and: [
{"waitingForLock" : true},
{"ns" : "edidatico.testes-cadastro"}
]
}
)

[tregubov-av]

I agree, very useful functionality.
I made an implementation in percona mongodb_exporter
Might be useful for you
issues: percona/mongodb_exporter#704
PR: percona/mongodb_exporter#706