I'm glad that this mod sparked some discussion about making Minetest more reliable with high uptime.
I don't know much about the topic but I have done some hasty profiling of the Minetest server with Massif showing that the memory representation of mapblocks are the biggest cause of memory usage, and it doesn't seem like the memory usage goes down when mapblocks should be unloaded. Of course whether it should keep mapblocks in memory for long periods of inactivity when no player is around or even online depends on how much RAM you have to spare for your server. Really it's the good old space-time tradeoff problem and what is good use of RAM for one person is a memory usage sink for another that makes me worried the server will OOM when combined with the other services running on the server.
As for performance issues, recently a friend who was playing on my server told me that there was significant delay when placing or breaking nodes on the server. I thought it was just his internet but the server had been running for 7 days and it was indeed less responsive than it should be. I restarted the server and it immediately went back to normal after that. Haven't investigated it further (though I don't really have the ability to keep a test server running for a long period of time with profilers attached), but the general advice from server owners seem to be regular restarts to freshen up the server which yeah, does point to some flaw somewhere in the Minetest server.
The fact this mod is even needed is probably evidence that Minetest suffers from undiscovered memory leaks.
The real long-term solution to the described problem, thus, is to investigate what on Earth is going wrong with Minetest.
Ideally, Minetest should be able to run for a long time with no memory issues.
I'm glad that this mod sparked some discussion about making Minetest more reliable with high uptime.
I don't know much about the topic but I have done some hasty profiling of the Minetest server with Massif showing that the memory representation of mapblocks are the biggest cause of memory usage, and it doesn't seem like the memory usage goes down when mapblocks should be unloaded. Of course whether it should keep mapblocks in memory for long periods of inactivity when no player is around or even online depends on how much RAM you have to spare for your server. Really it's the good old space-time tradeoff problem and what is good use of RAM for one person is a memory usage sink for another that makes me worried the server will OOM when combined with the other services running on the server.
As for performance issues, recently a friend who was playing on my server told me that there was significant delay when placing or breaking nodes on the server. I thought it was just his internet but the server had been running for 7 days and it was indeed less responsive than it should be. I restarted the server and it immediately went back to normal after that. Haven't investigated it further (though I don't really have the ability to keep a test server running for a long period of time with profilers attached), but the general advice from server owners seem to be regular restarts to freshen up the server which yeah, does point to some flaw somewhere in the Minetest server.
This might have been fixed by #14707, but I haven't tested it on my server yet. Minetest is always improving!