User and connection limits?

[dennisleedevelo]

Are there any limits on how many users can log into a Neo4j database (Enterprise Edition) concurrently?

Are there any limits on how many bolt sessions (via JavaScript Driver) can be open to a Neo4j database (Enterprise Edition) concurrently?

[michael_hunger]

What are your requirements?

It depends on some configurations settings in the server for this.

dbms.connector.bolt.thread_pool_keep_alive

The maximum time an idle thread in the thread pool bound to this connector will wait for new tasks.

dbms.connector.bolt.thread_pool_max_size

The maximum number of threads allowed in the thread pool bound to this connector.

dbms.connector.bolt.thread_pool_min_size

The number of threads to keep in the thread pool bound to this connector, even if they are idle.

dbms.threads.worker_count

Number of Neo4j worker threads.

[sandeepwww]

What are the default values for the above config?
I am unable to find these in my config file, not even commented.

[sandeepwww]

Option name	Default	Description
dbms.connector.bolt.thread_pool_min_size	5	The minimum number of threads that will always be up even if they are idle.
dbms.connector.bolt.thread_pool_max_size	400	The maximum number of threads that will be created by the thread pool.
dbms.connector.bolt.thread_pool_keep_alive	5m	The duration that the thread pool will wait before killing an idle thread from the pool. However, the number of threads will never go below dbms.connector.bolt.thread_pool_min_size .

[michael_hunger]

You can add them to the config.

[urjitgokhale]

Hey @michael.hunger,

What is the maximum supported value for thread_pool_max_size config setting? What all factors should one take into account to arrive at the optimal value that would be supported by the server (eg. the server capacity in terms of CPU/Memory etc? anything else?)

I see that I am running with the default value of 400 and I hit that limit frequently as I have quite a few clients connecting to my server. So I was planning on setting a higher value for this setting. But then I am not sure what should be the correct value? 1000? 10,000?
How do I arrive to the right value that my server will be able to handle?

On a side note - I also see that my CPU gets wedged at 100% when I hit this default limit of 400 and there are clients still trying to connect. What is the correlation between these two?

Thanks,
~ Urjit

[joehoeller]

Are we able to add multiple users w same login if we add multiple threads?