On 10/06/2016 06:20, Matt Hornsby wrote:
No matter the hardware or load test configuration, I see around 20-40
ms response times. The goal for the services that I am designing is
20ms and several thousand requests per second. The load tests that
Chris McCord and others have published suggest that I should be able
to expect 3ms or less when running localhost, but i'm not seeing
anything close to that.
This smells like a networking issue?
I would get a packet trace from the machine and check packet timing. I
wonder if you are seeing:
- Nagle, ie tcp_nodelay
- delayed ack (probably not because this is much larger)
A cursory github query on the phrase "nodelay" (elixir symbol should be
:nodelay) doesn't turn up any references in the phoenix repo... I guess
the correct search would be in cowboy. Again searching the cowboy repo
shows two examples in the tests (and some suggestions in bug reports),
but no other mention
I wonder if you try hacking your local phoenix code to turn on
tcp_nodelay if the extra millisecs delay disappears? (See search of
cowboy repo for examples)
Interesting... Perhaps Chris M could chime in?
Note, I found this helpful for quick and dirty testing (showed me that
name resolution of "localhost" takes half a ms on OSX...)
http://stackoverflow.com/questions/18215389/how-do-i-measure-request-and-response-times-at-once-using-curl
Ed
--
You received this message because you are subscribed to the Google Groups
"elixir-lang-talk" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To view this discussion on the web visit
https://groups.google.com/d/msgid/elixir-lang-talk/eb6f6c55-296a-2f8d-f1a0-eaa17bb5a6c5%40wildgooses.com.
For more options, visit https://groups.google.com/d/optout.
