Terrible performace with Keep-Alive

[xkrt]

Hi guys! I think I found a problem with Keep-Alive.

Test server:

open System
open System.Net
open Suave
open Suave.Types
open Suave.Http
open Suave.Http.Applicatives
open Suave.Http.Successful

let config = { Web.defaultConfig with bindings = [ HttpBinding.mk HTTP IPAddress.Any 6001us ] }
let data = String('x', 1024)

let app = GET >>= path "/" >>= (fun x -> printf "."; OK data x)

[<EntryPoint>]
let main _ =
    do Web.startWebServer config app
    Console.ReadLine() |> ignore
    printfn "done"
    0

Run Apache benchmark (from Windows 7) without Keep-Alive:

>ab -c 10 -n 1000 http://remote-host:6001/
...
Concurrency Level:      10
Time taken for tests:   0.882 seconds
Complete requests:      1000
Failed requests:        0
Total transferred:      1169000 bytes
HTML transferred:       1024000 bytes
Requests per second:    1133.67 [#/sec] (mean)
Time per request:       8.821 [ms] (mean)
Time per request:       0.882 [ms] (mean, across all concurrent requests)
Transfer rate:          1294.20 [Kbytes/sec] received

Connection Times (ms)
              min  mean[+/-sd] median   max
Connect:        0    1   0.4      1       2
Processing:     1    8   1.0      8      11
Waiting:        0    4   2.1      4      10
Total:          2    9   1.0      9      12

Percentage of the requests served within a certain time (ms)
  50%      9
  66%      9
  75%      9
  80%     10
  90%     10
  95%     10
  98%     11
  99%     11
 100%     12 (longest request)

Most important line: Requests per second: 1133.67 [#/sec] (mean)

Now lets run with Keep-Alive (-k):

>ab -k -c 10 -n 1000 http://remote-host:6001/
...
Concurrency Level:      10
Time taken for tests:   20.305 seconds
Complete requests:      1000
Failed requests:        0
Keep-Alive requests:    1000
Total transferred:      1193000 bytes
HTML transferred:       1024000 bytes
Requests per second:    49.25 [#/sec] (mean)
Time per request:       203.050 [ms] (mean)
Time per request:       20.305 [ms] (mean, across all concurrent requests)
Transfer rate:          57.38 [Kbytes/sec] received

Connection Times (ms)
              min  mean[+/-sd] median   max
Connect:        0    0   0.1      0       2
Processing:   194  202   3.7    201     212
Waiting:        0    1   0.6      1      10
Total:        194  202   3.7    201     212

Percentage of the requests served within a certain time (ms)
  50%    201
  66%    201
  75%    201
  80%    201
  90%    210
  95%    211
  98%    211
  99%    211
 100%    212 (longest request)

Requests per second: 49.25 [#/sec] (mean)

Note that remote server should be really remote host, on localhost this problem doesnt reproduce for me.

As remote host I was check Windows Server 2012R2 (.NET 4.5) and Ubuntu Server 15.10 with Mono (under docker with mono:latest image).

[xkrt]

Actually this problem reproduces somehow on localhost too (ab should be runned with http://127.0.0.1:6001/, not http://localhost:6001/ on Windows for unkown reason).

Without Keep-Alive I have ~2600 reqs/sec, with Keep-Alive ~1300 reqs/sec.

PS: Suave 0.33, .NET 4.5

[xkrt]

I just found #313.
I think this is same problem and it unrelated to libuv at all.

@haf run tests on Example project, I repeat it, but on remote host and with log level = info.
Server under Windows 2012R2, ab runned under Windows 7.

Without Keep-Alive:

>ab -c 15 -t 20 http://remote-host:8082/hello
...
Requests per second:    886.25 [#/sec] (mean)
...

With Keep-Alive:

>ab -k -c 15 -t 20 http://remote-host:8082/hello
...
Requests per second:    73.26 [#/sec] (mean)
...

If I run Example under Linux/Mono I have similar numbers.

Tests was on rev 88a8e6e
I think this is serious problem since all connections are persistent by default since HTTP 1.1

[ademar]

@xkrt Very interesting. I think a37f7ea solves the issue.

Do you want to give it another try ?

[xkrt]

@ademar great! now with Keep-Alive I have 7879 reqs/sec running Example console! Keep-Alive in action :)

FYI there is a problem running Example with this branch on Windows/.NET: haf/YoLo#1

[ademar]

Cool.

Regarding the other issue - Don't know if it is the case but the rake build
script will generate the required AssemblyVersionInfo files.

On Tuesday, 8 December 2015, Pavel Martynov notifications@github.com
wrote:

@ademar https://github.com/ademar great! now with Keep-Alive I have
7879 reqs/sec with Example console! Keep-Alive in action :)

FYI there is a problem running Example with this branch on Windows/.NET:
haf/YoLo#1 haf/YoLo#1

—
Reply to this email directly or view it on GitHub
#346 (comment).

Ademar Gonzalez
+1-647-891-3606
http://ademar.name
https://github.com/ademar

[xkrt]

Ok, I see, I just used build.cmd.

[haf]

Yeah, I could extend that code to support assemblies with no version... PR?

[xkrt]

@haf I see you replace Value with getValue() with last YoLo commit, I update YoLo dependency with #349

[haf]

Merged! Thank you