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I just posted some questions and recognized that up to 7 people viewed them before they appeared on questions front page.

Why does it take so long and who (and how) is viewing them, although they are not displayed?

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  • $\begingroup$ Sometimes (I think it happened more in the past) I have been surprised to see "new" questions appear with an answer. Time travel? $\endgroup$ – André Nicolas Dec 10 '13 at 0:08
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    $\begingroup$ It's always Caching. $\endgroup$ – Amelia Dec 10 '13 at 0:13
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Question lists are cached by SE servers. This means, the scripts fetching posts from the database don't actually talk to the database every time you hit refresh or navigate between pages. They wait until 1-2 minutes pass since their last sync, depending on the page (time intervals stated here). Digging into the database every time someone opens a SE page would cause high CPU load and make the sites slower for everyone.

Someone else may well see your question sooner than you, if their copy of question list is due for an update sooner. This user may have time to vote on the post, or maybe even answer it before you see your own question.

If you really can't wait to see it, try navigating to a different view, i.e., switch between active and newest. One may update faster than the other.

For gory details, see Does Stack Exchange use caching and if so, how?

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  • $\begingroup$ Thanks for your explanations and links... $\endgroup$ – draks ... Dec 10 '13 at 7:12

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