Discourse docker redis warning messages

188:M 13 Sep 04:27:11.292 # WARNING: The TCP backlog setting of 511 cannot be enforced because /proc/sys/net/core/somaxconn is set to the lower value of 128.

My question is, is this on the host or the docker? Because on the host it’s already 1024. I checked with cat /proc/sys/net/core/somaxconn

WARNING you have Transparent Huge Pages (THP) support enabled in your kernel. This will create latency and memory usage issues with Redis. To fix this issue run the command 'echo never > /sys/kernel/mm/transparent_hugepage/enabled' as root, and add it to your /etc/rc.local in order to retain the setting after a reboot. Redis must be restarted after THP is disabled.

My server is a multi-service service and I run many services on it, including other databases (mariadb) for instance. What are the consequences of disabling this on other services and databases?

WARNING overcommit_memory is set to 0! Background save may fail under low memory condition. To fix this issue add 'vm.overcommit_memory = 1' to /etc/sysctl.conf and then reboot or run the command 'sysctl vm.overcommit_memory=1' for this to take effect.

This one I fixed with the command on the host fine. But I feel like there should be more documentation on this warnings, and how they affect our systems. sorry if my questions are dumb…

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discourse-setup is meant to deal with issue like this these days.

Not sure if this is an issue anymore @pfaffman

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discourse-setup doesn’t do the THP, maxconn, or overcommit_memory stuff; it just adds swap if RAM is <=2GB. I set those things in my setups but I haven’t looked carefully to see if it really helps this message go away. It seems like I see those messages scrolling by?

I presume that it’s on the host, but this makes me wonder.

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