Why can't D language framework play best?

[Jacob Carlborg]

On 2020-05-08 10:13, zoujiaqing wrote:
> We have been continuously optimizing the performance of hunt library io 
> module, but have not been as high as AspCore、Rust and Java.
> 
> https://www.techempower.com/benchmarks/#section=test&runid=9e7a6863-b92e-4079-a2a9-324426369751&hw=ph&test=plaintext 
> 
> 
> What good ideas do you have to offer?

I think 18 out of 404 (plain text) and 8 out of 409 (JSON serialization) 
is pretty good. Compare that with vibe.d, it's down on 139, or something 
like that.

I haven't used Hunt, but I did have a brief look at the code base. It 
seems very class centric. That means heap allocation (which are slow) 
and access through indirection, which are at least slower than a direct 
access. Keep in mind the D's GC is stop-the-world. Would be interesting 
to see a benchmark with the GC turned off. Or using multiple processes 
(assuming it's not already used) instead of multiple threads.

I think as much of possible should be based on structs. It always 
simpler to turn a value type into a reference type (by embedding it in a 
class) then doing the opposite.

I haven't done any benchmarks, but when it comes to allocations it 
sounds like a request local region allocator, possible backed with a 
free list, would be efficient. The region allocator could first use a 
static array as its buffer, then fall back to allocating on the heap 
when the static buffer is full.

-- 
/Jacob Carlborg