0

I have a VM setup on Azure in "South Brazil" location hosting a WCF service. Although I'm also in Brazil, latency to reach my service in the VM is ~200ms. I have the same service deployed in two other Brazilian hosts and latency to both of them is <60ms.

I've also seen people doing some tests on other Azure datacenters, and latency seems to always be ~50ms as well when near them.

I initially thought that it could be a VM size-related problem, but changing the size to D3 (which is kinda overkill to my service: CPU stays at only ~5%) didn't help at all, latency stayed the same.

Is this normal for South Brazil datacenters, or can it be something else?

Note that as I can't ping an Azure VM, I'm measuring the time in C# to TcpClient.Connect on port 80 with a StopWatch.

Thanks in advance.

closed as too broad by EEAA Dec 13 '15 at 23:41

Please edit the question to limit it to a specific problem with enough detail to identify an adequate answer. Avoid asking multiple distinct questions at once. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

  • Did you measure latency to the "other brazilian hosts" (<60ms) using TcpClient.Connect as well? – Jukka Dec 13 '15 at 20:08
  • yes, I've tried both ping and TcpClient.Connect on those others. – andre_ss6 Dec 13 '15 at 20:37
  • Okay, have a look at @EEAA's answer. You could also try azurespeedtest.azurewebsites.net and see what you get – Jukka Dec 13 '15 at 20:44
  • @Jukka Yes, I've seen that website before. Strangely enough, it reports ~200ms for North Central US and >400ms for Brazil South. Sigh. – andre_ss6 Dec 14 '15 at 1:28
1

There is no guaranteed latency on the public internet. Nor is there a way for any of us to gauge if the latency you're seeing is a result of network congestion or some other issue.

You'll need to take this up with Azure and your ISP.

  • Yes I know. But I only wanted to know if this is consistent with other people hosting VM's on Brazil South's datacenters. If it's not, then I would start trying to troubleshoot the issue. – andre_ss6 Dec 13 '15 at 20:58
  • I've seen from 5ms to 200ms. Not really an exact science. It's all about the route. – Bruno Faria Dec 13 '15 at 23:15
  • I see. Thanks for your answer. Do you have any suggestion of anything I can try, or anywhere I should look for, before contacting Azure support? – andre_ss6 Dec 14 '15 at 1:27
  • Test latency to your server from as many different ISPs as you can get access to. – EEAA Dec 14 '15 at 1:28

Not the answer you're looking for? Browse other questions tagged or ask your own question.