I know that Discourse setup provides sane defaults for most occasions nowadays, but I still want to ask some guidance on optimal settings. It seems that we will get a hosting partner that provides us with the server and what is on the table is this VPS: 6x vCore CPUs (Xeons @ 2.40GHz, I beleive) 8…

Thanks Matt. Crystal clear and informative, as usual. Here is a some more nerd porn. Our API requests for this year. This is what it looks like when there is a hockey league transfer deadline on the 15th of Feb at 23:59 local time. [image]

What tools are you using for monitoring the api requests, which is shown from your image?

If I’m not mistaken, that’s Discourse’s built in report visualizer. Go to yoursite.com/admin, then click any of the statistic titles.

[image] codinghorror: The usual, which is DB gets 1/4 of memory Up to two unicorns per “real” CPU core (I’d limit to 8 for now though) Bump. So are you saying 8 Unicorns is the upper limit on any server? I have a server with 8x CPU and was thinking changing the config to use 16?

Maybe, it depends how much traffic you have. 16 unicorns sitting around doing nothing and waiting for incoming requests would not get you much.

800k-1.2m pageviews/month. Discourse runs buttery smooth most of the time but then if we ever get 300 concurrent users it grinds to a halt. Already have db_shared_buffers configured to 25% of the host’s 32gb RAM, looking for more possible fixes.

Sounds like it could help. Please report back.

Done. We’ll see, not expecting another traffic spike for awhile.

I am currently using 10 unicorns (IIRC) on my 6-core instance at UpCloud. This gets me above 400+ concurrents. We’ll see in February what it takes to choke this.

Neat. I guess I’m just wondering if there’s a tipping point where having a too high number of unicorns is actually detrimental.

Optimizing the number of Unicorns and buffer size

Support Self-hosting

sam (Sam Saffron) October 26, 2017, 4:09am 16

You know, there is only one way to find out … measure.

Topic		Replies	Views
High CPU usage (Ruby) Support server-resources	20	1053	February 3, 2025
Recommendation for number of workers: cores × 2? Self-hosting	16	700	April 29, 2025
Limiting the number of unicorns, memory usage and swapping Self-hosting server-resources	4	1021	November 11, 2023
Digital Ocean Droplet Size Self-hosting	6	1304	August 19, 2019
Tuning a Discourse server for performance Self-hosting hosting	11	3085	April 4, 2022

Optimizing the number of Unicorns and buffer size

Related topics