dlang vibe.d RESTful服务性能

Question

Thank you for your assistance.

Question:
Why does my REST service seem to perform so poorly using rest interfaces in dlang vibe.d when compared to creating request handlers manually?

More Information:
I have been prototyping a RESTful service using the vibe.d library in dlang. I'm running a test where a client sends GET and POST requests to the server with a payload of some given size, say 2048 byte (ie the GET response would have 2k, the POST request would have 2k).

I'm using the " registerRestInterface " and " RestInterfaceClient " API in the vibe.d library to create my server and client sort of like this...

Server:

auto routes = new URLRouter;      

registerRestInterface(routes, new ArtifactArchive());

auto settings = new HTTPServerSettings();

settings.port = port;
settings.bindAddresses = [host];
settings.options |= HTTPServerOption.distribute;

listenHTTP(settings, routes);

runEventLoop();

Client:

IArtifactArchive archive = new RestInterfaceClient!IArtifactArchive(endpoint)  
IArtifactArchive.Payload result;  
result = archive.getContents(info.FileDescriptor, offset, info.BlockSize);

I'm not doing anything fancy in my interface. Just filling a byte array and passing it along. I know performance depends on many different things; however I seem to see about 160kB transfer rate when using REST interfaces in vibe.d and roughly 5MB transfer rate when using manual http request handlers like this:

void ManualHandleRequest(HTTPServerRequest req, HTTPServerResponse res) ...  
listenHTTP(settings, &ManualHandleRequest);

I really like the REST interface API, but I can't suffer that kind of performance loss in order to use it. Any thoughts on why it seems so much slower than the other method? Perhaps I'm configuring something wrong or missing something. I am somewhat new to the D programming language and the vibe.d library.

Thank you for your time!

Answer 1

I suspect that with custom request handler you actually write response as a byte array. REST interface generator serializes all return data into JSON by default which creates huge overhead compared to raw array.

This is just a random guess though, I need to see actual REST method implementation to say for sure and/or propose solution.