Slow downloads on iOS

Bryan O’Sullivan's Avatar

Bryan O’Sullivan

08 Sep, 2020 04:03 PM

Hi folks, I’m using the iOS app, and I find that when I scroll around, it often takes 5-30 seconds for map tiles to download.

Needless to say, this makes using the app a huge exercise in patience, and is very frustrating.

My internet connection is not the issue, as I have a symmetric gigabit connection and every other mapping app works fine.

Are you aware of this problem? And if so, do you have a schedule to fix it?

  1. Support Staff 1 Posted by Ben Lantow on 08 Sep, 2020 04:54 PM

    Ben Lantow's Avatar

    Thanks for the feedback,
    Fortunately, there isn't a persistent issue here. MapBuilder Tiles are based on a vector data set and have to be rendered. The last couple days and a few days last week due to fires in California and across the US our servers have been experiencing unprecedented volumes including our tile server. We've spun off some extra servers but still the volume of users has hit 6-7x our normal on several days.

    I'm so sorry you are having that experience. Just to be sure your experience is related to high server loads can you tell give us some details, specifically when you were having this issue?

    As an alternative if you plan or travel a lot in one area, you can just download that area for offline use, our app looks to downloaded tiles first.


  2. 2 Posted by Bryan O'Sulliva... on 08 Sep, 2020 04:58 PM

    Bryan O'Sullivan's Avatar

    Thanks for the quick reply, Ben.

    I’ve been seeing this more or less continuously for days. I’ve been using CalTopo more than usual due to the fire layers (thank you for building that feature!).

    It doesn’t seem to matter which layers or overpays I select, when it comes to performance.


  3. Support Staff 3 Posted by akaufmann on 08 Sep, 2020 05:38 PM

    akaufmann's Avatar


    This sounds really odd to me. If you turn off all overlays and stacked layers and select "OpenStreetMap" as your base map, do you still slow load times?

    What device are you using?


  4. akaufmann closed this discussion on 08 Sep, 2020 05:38 PM.

  5. Ben Lantow re-opened this discussion on 08 Sep, 2020 05:44 PM

  6. 4 Posted by Bryan O'Sulliva... on 09 Sep, 2020 04:34 AM

    Bryan O'Sullivan's Avatar

    Things perform much better with wind plot and fire activity turned off.

    With just wind plot alone turned on, panning and zooming can take 10-15 seconds to render a screen fully.

    With wind plot off and fire activity on, it’s not as fast as with the base layer alone, but the fetch+render time is more like a couple of seconds.

    This suggests that perhaps the wind plot is the smoking gun?


  7. Support Staff 5 Posted by Ben Lantow on 09 Sep, 2020 04:06 PM

    Ben Lantow's Avatar

    Hi Bryan,
    The overlays are definitely a little more intensive (wind being realtime, means it is rendered on demand, fire activity lately has been rendered and cached a ton, its under extraordinary loads). If you don't mind I'd like to ask a couple other questions.

    Do you see any lag with the Open Street Map layer? (that isn't hosted on our server)
    When you compared to Map Builder Topo layer is it about the same or noticable?
    When you turn on overlays do you see the base layers immediately while the overlays take time to load or does the entire map pause until the overlay has loaded?

    Any other areas of sluggishness?


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