Mongo staled with too much insertions - mongodb

Question

I trying to use mongodb to run a multiagent simulation.
I have one mongo instance in the same server that runs the simulation program, but when I have too much agents (~100.000 in 10 simulation steps) the mongodb becomes stalled during seconds.
The code for insert data in mongo is similar to:
if( mongo_client( &m_conn , m_dbhost.c_str(), m_dbport ) != MONGO_OK ) {
cout << "failed to connect '" << m_dbhost << ":" << m_dbport << "'\n";
cout << " mongo error: " << m_conn.err << endl;
return;
}
bson_init( &b );
bson_append_new_oid( &b, "_id" ) != BSON_OK );
bson_append_double( &b, "time", time );
bson_append_double( &b, "x", posx );
bson_append_double( &b, "y", posy );
bson_finish( &b );
if( mongo_insert( &m_conn , ns.c_str() , &b, NULL ) != MONGO_OK ){
cout << "failed to insert in mongo\n";
}
bson_destroy( &b );
mongo_disconnect( &m_conn );
Also, during the simulation, If I try to access using the mongo-shell, I also get errors:
$ mongo
MongoDB shell version: 2.4.1
connecting to: test
Wed Apr 3 10:10:24.870 JavaScript execution failed: Error: couldn't connect to server 127.0.0.1:27017 at src/mongo/shell/mongo.js:L112
exception: connect failed
After the simulation is ended, the mongo shell gets responsive again, and I can check that there is data in the database but it is discontinued. In the example, the agent m0n999 saved only 6 of 10 steps:
> show dbs
dB0B7F527F0FA45518712C8CB27611BD7 5.951171875GB
local 0.078125GB
> db.ins.m0n999.find()
{ "_id" : ObjectId("515bdf564c60ec1e000003e7"), "time" : 1, "x" : 1.1, "y" : 8.1 }
{ "_id" : ObjectId("515be0214c60ec1e0001075f"), "time" : 2, "x" : 1.2000000000000002, "y" : 8.2 }
{ "_id" : ObjectId("515be1c04c60ec1e0002da3a"), "time" : 4, "x" : 1.4000000000000004, "y" : 8.399999999999999 }
{ "_id" : ObjectId("515be2934c60ec1e0003b82c"), "time" : 5, "x" : 1.5000000000000004, "y" : 8.499999999999998 }
{ "_id" : ObjectId("515be3664c60ec1e000497cf"), "time" : 6, "x" : 1.6000000000000005, "y" : 8.599999999999998 }
{ "_id" : ObjectId("515be6cc4c60ec1e000824b2"), "time" : 10, "x" : 2.000000000000001, "y" : 8.999999999999996 }
>
How can solve this problem? How can avoid the lost of connections and recover from mongo stalls?
UPDATE
I'm getting in the global log errors like:
"Wed Apr 3 11:53:00.379 [conn1378573] error: hashtable namespace index max chain reached:1335",
"Wed Apr 3 11:53:00.379 [conn1378573] error: hashtable namespace index max chain reached:1335",
"Wed Apr 3 11:53:00.379 [conn1378573] error: hashtable namespace index max chain reached:1335",
"Wed Apr 3 11:53:00.379 [conn1378573] error: hashtable namespace index max chain reached:1335",
"Wed Apr 3 11:53:00.379 [conn1378573] end connection 127.0.0.1:40748 (1 connection now open)",

Answer 1

I solved the problem, it has two errors:
I was creating too much collections. I changed from one collection per Agent, to only on collection per simulation proccess.
I was creating too much connections. I changed from one connection per Agent iteration, to only one connection per simulation step.