mongodb/jstests/sharding/shard_kill_and_pooling.js

//
// Tests what happens when a shard goes down with pooled connections.
//

// Run through the same test twice, once with a hard -9 kill, once with a regular shutdown

for ( var test = 0; test < 2; test++ ) {

var killWith = (test == 0 ? 15 : 9);
var options = { separateConfig : true };

var st = new ShardingTest({shards : 2, mongos : 1, other : options});

// Stop balancer to eliminate weird conn stuff
st.stopBalancer();

var mongos = st.s0;
var coll = mongos.getCollection("foo.bar");
var db = coll.getDB();

//Test is not valid for Win32
var is32Bits = ( db.serverBuildInfo().bits == 32 );
if ( is32Bits && _isWindows() ) {

    // Win32 doesn't provide the polling interface we need to implement the check tested here
    jsTest.log( "Test is not valid on Win32 platform." );

}
else {
    
    // Non-Win32 platform

    assert.writeOK(coll.insert({ hello: "world" }));

    jsTest.log("Creating new connections...");
    
    // Create a bunch of connections to the primary node through mongos.
    // jstest ->(x10)-> mongos ->(x10)-> primary
    var conns = [];
    for ( var i = 0; i < 50; i++) {
        conns.push(new Mongo(mongos.host));
        assert.neq( null, conns[i].getCollection(coll + "").findOne() );
    }
    
    jsTest.log("Returning the connections back to the pool.");
    
    for ( var i = 0; i < conns.length; i++ ) {
        conns[i] = null;
    }
    // Make sure we return connections back to the pool
    gc();
    
    // Don't make test fragile by linking to format of shardConnPoolStats, but this is useful if
    // something goes wrong.
    var connPoolStats = mongos.getDB("admin").runCommand({ shardConnPoolStats : 1 });
    printjson( connPoolStats );
    
    jsTest.log("Shutdown shard " + (killWith == 9 ? "uncleanly" : "" ) + "...");
   
    // Flush writes to disk, since sometimes we're killing uncleanly
    assert( mongos.getDB( "admin" ).runCommand({ fsync : 1 }).ok );
    
    MongoRunner.stopMongod( st.shard0, killWith );
    
    jsTest.log("Restart shard...");
    
    st.shard0 = MongoRunner.runMongod({ restart : st.shard0, forceLock : true });
    
    jsTest.log("Waiting for socket timeout time...");
    
    // Need to wait longer than the socket polling time.
    sleep(2 * 5000);
    
    jsTest.log("Run queries using new connections.");
    
    var numErrors = 0;
    for ( var i = 0; i < conns.length; i++) {
        var newConn = new Mongo(mongos.host);
        try {
            assert.neq( null, newConn.getCollection("foo.bar").findOne() );
        } catch (e) {
            printjson(e);
            numErrors++;
        }
    }
    
    assert.eq(0, numErrors);

} // End Win32 check

st.stop();

jsTest.log("DONE test " + test);

} // End test loop

jsTest.log("DONE!");