https://chat.stackexchange.com/ and the individual sites has significant delay in data synchronization. For example Stephen Kitt's chat account shows 997 bronze medals (and it was 996 yesterday),

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while his network account has shown 999 since yesterday:

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How does the delay happen, while the individual sites don't have visible delay between themselves?

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Is an implementation that can avoid the delay too expensive?

I am interested in data engineering, so I would like to hear data engineering side of the story


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  • The answer will almost certainly be caching. Presumably, the chat profile is only updated periodically to avoid spamming the SE servers with API requests. You can usually find the answer here: shouldiblamecaching.com (this is a joke). – terdon May 28 at 13:50
  • Interestingly, while the flair image is updated every 24-36 hours and the (data behind the) chat profile page is updated hourly, I'm still seeing 999 bronze badges in the former and 997 on the latter (surely not because of my local cache and likely not even because of IP-based server-side cache (if any)). – fra-san May 30 at 22:24
  • @fra-san I noticed the same thing, but forcing a local refresh updated the value on the chat profile, so it appears this is due to a local cache. – Stephen Kitt May 31 at 12:09
  • @StephenKitt I can't reproduce it anymore (I see you at 1000 everywhere now), but I'm quite sure I've seen 997 bronze badges both using a fresh browser session and requesting a screenshot of your chat profile to an online service (trying to also rule out a server-side caching issue). – fra-san May 31 at 13:08
  • @fra-san right, so it would appear that there are both server-side and local caches. – Stephen Kitt May 31 at 13:26
  • @StephenKitt your network silver medals are 888 now – Tim Jun 2 at 12:13
  • @Tim so they are! – Stephen Kitt Jun 2 at 12:23

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