Worker threads and min/ max circuits

[teddyrogers]

In, "configuration.json", I think these settings are self explanatory however, to remove ambiguity, please can you elaborate/ explain the settings below?

• "ipv8", "worker_threads"
• "tunnel_community", "min_circuits"
• "tunnel_community", "max_circuits"

Are the default values used conservative, to be applicable for all system types?

For more modern/ high end systems would there be any benefit increasing these values?

[qstokkink]

These are low-level settings and you need to know about object pools for these settings to make (conceptual) sense. I'll try my best to give you the ropes.

There are essentially two pools here. The first is the thread pool that handles network data (worker_threads) and the second pool consists of the anonymizing circuits through which anonymous downloads go (min_circuits and max_circuits).

In both cases, having too few objects (or threads) in a pool can underutilize your CPU. If you allocate too many threads, they will just be idle and cause management overhead. This overhead may be in simple thread management but - in the case of circuits - can also cause a lot of useless network messages.

The settings that you found control the size of the pools. For the number of threads handling network information (worker_threads), we can simply set the number of threads that wait for network messages to arrive. However, the anonymizing circuits take a bit of time to create. So we allow them to fluctuate between a minimum and maximum number (min_circuits and max_circuits respectively). As a rather important aside, Tribler waits for the minimum number of circuits to be available before your downloads start.

By default, we set the maximum number of threads to 1 thread per anonymizing circuit, for the maximum number of circuits. More threads doesn't make much sense (at best, this will only marginally improve your speed beyond this ratio). If you're willing to sacrifice the time it takes for Tribler to start and some bandwidth, you can increase the minimum number of circuits. However, setting the minimum circuits to anything beyond 8 doesn't do anything for download speed, from my testing at least. The default of 8 for the maximum circuits should already accomodate that (the minimum should never be higher than the maximum).

[teddyrogers]

@qstokkink thank you for the informative reply, that helps clarify some details.