Configure mongodb property maxWaitQueueSize in Spring boot application?

Question

I get the error com.mongodb.MongoWaitQueueFullException: Too many threads are already waiting for a connection. Max number of threads (maxWaitQueueSize) of 500 has been exceeded. while doing a stress test on my application.

So I am thinking of configuring the maxWaitQueueSize property via configuration.

I am using spring boot to configure mongodb connection. I am using @EnableAutoConfiguration in my Application and I have declared only spring.data.mongodb.uri=mongodb://user:password@ip:27017 in the application.properties file.

How do I configure the maxWaitQueueSize property with spring boot?

How do I decide a good value for the maxWaitQueueSize?

Answer 1

If you're using MongoDB 3.0+, you can set waitQueueMultiple in your mongouri :

spring.data.mongodb.uri=mongodb://user:password@ip:27017/?waitQueueMultiple=10

waitQueueMultiple is a number that the driver multiples the maxPoolSize value to, to provide the maximum number of threads allowed to wait for a connection to become available from the pool.

How do I decide a good value for the maxWaitQueueSize?

It's not directly related to MongoDB but you can read more about Pool Sizing in Hikari github wiki.

Answer 2

In com.mongodb.MongoClientURI, you can find the parameters which can be used in MongoClientOption.

        if (key.equals("maxpoolsize")) {
            builder.connectionsPerHost(Integer.parseInt(value));
        } else if (key.equals("minpoolsize")) {
            builder.minConnectionsPerHost(Integer.parseInt(value));
        } else if (key.equals("maxidletimems")) {
            builder.maxConnectionIdleTime(Integer.parseInt(value));
        } else if (key.equals("maxlifetimems")) {
            builder.maxConnectionLifeTime(Integer.parseInt(value));
        } else if (key.equals("waitqueuemultiple")) {
            builder.threadsAllowedToBlockForConnectionMultiplier(Integer.parseInt(value));
        } else if (key.equals("waitqueuetimeoutms")) {
            builder.maxWaitTime(Integer.parseInt(value));
        } else if (key.equals("connecttimeoutms")) {
            builder.connectTimeout(Integer.parseInt(value));
        } else if (key.equals("sockettimeoutms")) {
            builder.socketTimeout(Integer.parseInt(value));
        } else if (key.equals("autoconnectretry")) {
            builder.autoConnectRetry(_parseBoolean(value));
        } else if (key.equals("replicaset")) {
            builder.requiredReplicaSetName(value);
        } else if (key.equals("ssl")) {
            if (_parseBoolean(value)) {
                builder.socketFactory(SSLSocketFactory.getDefault());
            }
        }