Re: [libmicrohttpd] Where are http requests queued?

[Bob Furber]

On 15-05-05 03:09 AM, Christian Grothoff wrote:
> If your handler routine is reasonably fast, it can be difficult to 
> stress-test an MHD server with just a single client... 

I can get MHD on our ARM server to back up at about 150 (27 byte) 
requests/s sent by a LinuxPC on the same LAN. That is, if the client 
bombards the server at this rate for about a minute, and then posting 
requests is stopped. However, 1000 to 2000 replies are returned by the 
server AFTER sending requests has ceased.

> I'm not sure where you put the sleep(), but you may have them in the 
> TCP listen() queue of the operating system. That's a good place for 
> them if MHD can temporarily not catch up, you just want to keep that 
> queue short enough that client's do not regularly time out while in 
> the queue.

Ah! So, the OS (Linux, in this case) has a TCP listen queue! Doh! I was 
unaware. This is a good clue for further investigation.

But, I am still puzzled by the limit of 6 concurrent MHD threads? Why 6, 
not 5, 7...? Is this modifiable? Would there be any benefit to 
increasing or decreasing this number?

Thanks,

Bob Furber