5 ms·

None? Why would every button press require a full rtt?

gsich 5y ago
>that 200ms rtt does matter to users. it becomes very noticeable. especially when you're writing an app, not a brochure site. You need to tree shake so you're not serving a huge spa all at once. Because this implies that.
- ehutch79 5y ago
  No it doesn't. at all. Page load speeds by themselves can be painful. Open devtools and have your browser throttle to poor 3g speeds. Try browsing around. even well optimized sites. Now try uploading a couple dozen files through an api. This is legit what some users deal with. In New York state even, you don't need to go that far to find poor connectivity. Even if all your users have awesome home connections, think sales people taveling to a client. or on site inspections of a manufacturer in a warehouse that's mostly metal and has bad wifi.
  - gsich 5y ago
    Then what does the 200ms have do with "writing an app"?
    - ehutch79 5y ago
      Apologies, your username looks like the one that tossed that number out as a what they assumed was a high number. 200ms latency isn't that bad, but I'm seeing more 800-2000ms latencies with some users depending on physical location. at some point latency kills usability. Especially when trying to get through a complicated QA or inventory process.
      - withinboredom 5y ago
        That latency is literally impossible unless they’re up in space somewhere, beyond satellite orbit. Your latency is most likely caused by CPU on low-end devices. A CDN won’t help you with that (and probably be harmful having to manage another TCP connection).
        simfree 5y ago
        I see latency spike like this often on T-Mobile LTE. One second your under 40ms ping, then your next ping clocks in at 794ms or 2100ms despite having good signal strength.
        nijave 5y ago
        I few years back I was seeing about 15-30s latency on 2G EDGE. Overloaded links can have high latency due to queuing which CDNs tend to help
        ehutch79 5y ago
        Any latency over he speed of light is possible. In this case you’re seeing people in bad places, like rural China, or Long Island...
  - Dylan16807 5y ago
    If you're on 3G I would expect sites to load in a similarly bad way with or without an extra most of 200ms of RTT.
    - ehutch79 5y ago
      The throttling in dev tools is meant to represent that latency...
      - Dylan16807 5y ago
        If setting it to 3G is supposed to represent just 200ms latency, that's going to give you a very exaggerated and misleading impression of how bad it is. It's a meaningless test. I thought you were giving an example of how bad connections can get, and saying that the extra latency would make it worse, but in that situation it's a drop in the bucket.

>that 200ms rtt does matter to users. it becomes very noticeable. especially when you're writing an app, not a brochure site. You need to tree shake so you're not serving a huge spa all at once. Because this implies that.

ehutch79 5y ago
No it doesn't. at all. Page load speeds by themselves can be painful. Open devtools and have your browser throttle to poor 3g speeds. Try browsing around. even well optimized sites. Now try uploading a couple dozen files through an api. This is legit what some users deal with. In New York state even, you don't need to go that far to find poor connectivity. Even if all your users have awesome home connections, think sales people taveling to a client. or on site inspections of a manufacturer in a warehouse that's mostly metal and has bad wifi.
- gsich 5y ago
  Then what does the 200ms have do with "writing an app"?
  - ehutch79 5y ago
    Apologies, your username looks like the one that tossed that number out as a what they assumed was a high number. 200ms latency isn't that bad, but I'm seeing more 800-2000ms latencies with some users depending on physical location. at some point latency kills usability. Especially when trying to get through a complicated QA or inventory process.
    - withinboredom 5y ago
      That latency is literally impossible unless they’re up in space somewhere, beyond satellite orbit. Your latency is most likely caused by CPU on low-end devices. A CDN won’t help you with that (and probably be harmful having to manage another TCP connection).
      - simfree 5y ago
        I see latency spike like this often on T-Mobile LTE. One second your under 40ms ping, then your next ping clocks in at 794ms or 2100ms despite having good signal strength.
      - nijave 5y ago
        I few years back I was seeing about 15-30s latency on 2G EDGE. Overloaded links can have high latency due to queuing which CDNs tend to help
      - ehutch79 5y ago
        Any latency over he speed of light is possible. In this case you’re seeing people in bad places, like rural China, or Long Island...
- Dylan16807 5y ago
  If you're on 3G I would expect sites to load in a similarly bad way with or without an extra most of 200ms of RTT.
  - ehutch79 5y ago
    The throttling in dev tools is meant to represent that latency...
    - Dylan16807 5y ago
      If setting it to 3G is supposed to represent just 200ms latency, that's going to give you a very exaggerated and misleading impression of how bad it is. It's a meaningless test. I thought you were giving an example of how bad connections can get, and saying that the extra latency would make it worse, but in that situation it's a drop in the bucket.