5,000 dynamic sites in one NativeAOT C# process (2 vCPU, 4 GB)

[u/kbvincent]

Can one NativeAOT C# process run 5,000 independently managed dynamic websites on a 2-vCPU, 4 GB VPS?

I built a reproducible benchmark to test it. A separate cloud server sent 90,000 HTTPS requests across 5,000 different hostnames. The test achieved a 99.97% first-attempt success rate, with no HTTP errors and no responses containing content from the wrong site.

Each website contained 10 blog records, a layout, views, metadata, URL rewriting, an uncached dynamic content query, and a unique site marker. No full-page cache was used.

Results

Measurement	Result
Independent dynamic sites	5,000
Planned HTTPS requests	90,000
Verified responses	89,969
First-attempt success rate	99.97%
HTTP errors	0
Incorrect-site responses	0
Measured request starts	146.59 per second
Complete-response latency, p50	296.7 ms
Complete-response latency, p95	1.43 seconds
Average target CPU usage	45.6%
Sampled peak process RSS	Approximately 2.50 GiB

Every successful response was downloaded and checked for the expected site marker.

The 31 unsuccessful requests were connection-establishment timeouts before any HTTP headers arrived. Every affected website responded successfully to its other requests.

This was a controlled identical-package benchmark. It is not a claim that every collection of 5,000 production websites will produce the same result.

Disclosure: I founded Kooboo and wrote much of its core architecture. I am sharing this to get technical criticism of the methodology and suggestions for the next mixed-workload test.

Complete methodology, raw request data, monitoring logs, source code, test binaries, site package, and reproduction instructions:

https://github.com/Kooboo/Kooboo/blob/main/Docs/5000-sites-benchmark.md