[bob1029]

I don't know of any, but I have been building prototypes in .NET Core 3+ that give me confidence in using this platform as a basis for an ultra-low-latency business system.

The biggest issue would be avoiding heap alloc, but that is actually not too difficult if you manage your data well enough. Most transactions in this business can be defined in terms of structs that are <1kb in size.

One other approach I have started to look at is sacrificing an entire high-priority thread to handling well-batched transactions (or extremely important timers) so that I never have to yield to the OS. In HFT, you always get an entire physical server to yourself, so eating 1 out of 32 threads is not a huge deal. In testing of this idea, I have found that I am able to reliably execute timers with accuracy of around 1/10th of a microsecond.

Java probably has more optimizations around GC suppression, but I feel like avoiding allocation in the first place is the most important bit. I believe there are already some ways to trick .NET into not running GC.

[gher-shyu3i]

Out of curiosity, what is the domain for the prototypes you're building?

[bob1029]

For now, I have been using this to test a toy/custom 2d client-server framework. All client events are piped to the server and processed in 1 gigantic ring buffer. This allows for ridiculous amounts of throughput due to batching effect. I am also using recurring, high-precision timers scheduled per client for purposes of triggering redraws and other important events as appropriate. This allows for complete decoupling of the event handling and client rendering pipelines. The breakdown is something like:

1 thread for ultra-low-latency timer execution

1 thread for processing the actual client event ring buffer, producing a consistent snapshot after each microbatch execution.

14+ threads for servicing HTTP requests (i.e. enqueuing client events), timers and redrawing client views using the near-real-time snapshots of business state.

My thinking is that if I can build something in this domain that is satisfactory, I could consider bringing it to an HFT firm as well.