Default Redis setting causes Out of Memory crashes

[steven-harper-ot]

Environment

self-hosted (https://develop.sentry.dev/self-hosted/)

Steps to Reproduce

1. Have plenty of CPU and RAM (16 cores) - 128gb
2. Have a busy server
3. Watch RAM usage by Redis climb to 70% of the total RAM
4. Other non Redis tasks tip the usage up to 100%
5. See that the OOM process clears down most of the processes
6. Find that you can't ssh on to the server, and after reboot; everything is a mess

Expected Result

A busy server can run for multiple hours without infinity growing in RAM

Actual Result

The busy server allows Redis to use most of the Ram, and other processes push it to 100%.

We have capped it at about 40% redis.conf

maxmemory 45gb

I would suggest being able to set this as a sensible number by percentage would be great, and shipping at infinite is bad

maxmemory 0

Product Area

Settings

Link

No response

DSN

No response

Version

25.11.1

[linear[bot]]

ENG-6057

[getsantry[bot]]

Assigning to @getsentry/support for routing ⏲️

[aldy505]

We have this PR if you want to provide some arguments on why we should merge it https://github.com/getsentry/self-hosted/pull/3907

I personally set it to somewhere on 16GB mark, but that would be horrendous for folks running a standard spec server.