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How does someone get to cast more than 40 votes in a day?

The daily vote limit appears to be subject to a race condition which could potentially defeat the limit. When I vote on a post, the system seems to count the vote against the post score before it counts against my vote limit, rather than acting as an atomic transaction, and this appears to be exploitable under a high-latency Internet connection (the network I was working from at the time randomly stalls for several seconds waiting for a response, possibly due to faulty on-site routing).

This is manifested as a substantial delay in getting the "you have x votes left today" warning: If I quickly cast more than x votes before this warning is displayed again, I can exceed the daily vote limit—a time-of-check-to-time-of-use bug. The result is the following (although I immediately retracted the extra vote):

41 votes in a day caused by non-atomic vote scoring

Can someone look into this?

Edit: Upon casting the final vote before the clock rolled over, I got "Daily vote limit reached; vote again in 36 seconds." I apparently got confused over the message, but there did seem to be some sort of anomaly with the way votes were being counted, as if the post score update and daily vote count update were not an atomic operation...

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    Interesting find. I never really understood the point of having limits on voting. Seems counter productive. – chown Sep 25 '12 at 1:13
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    During the very early days of the site, there weren't any limits, @chown. Folks... Had fun with that. One particularly blatant example involved a script that up-voted everything. Post something, get an up-vote. Talk about rep inflation... – Shog9 Sep 25 '12 at 1:38
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    @Shog9 Are you talking about this? stackoverflow.com/questions/21064/massive-reputation-jump – Mysticial Sep 25 '12 at 1:50
  • That's the one, @Mysticial - good find! – Shog9 Sep 25 '12 at 1:52
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    @Mysticial: That post is deleted. – Mechanical snail Sep 25 '12 at 2:10
  • @Mechanicalsnail: yes, it dates back to the Stack Overflow private beta - it's been deleted for a very long time now. – Shog9 Sep 25 '12 at 2:11
  • @Shog9 Shouldn't it be migrated to meta rather than deleted then? – Mechanical snail Sep 25 '12 at 2:14
  • If true, then you're saying the limitation is client side? That can't be true, as then it would easily be abused on any internet connection. – Arjan Sep 25 '12 at 2:15
  • @Mechanicalsnail: it was deleted by its author, long long before Meta existed. – Shog9 Sep 25 '12 at 2:16
  • Deleting my answer in response to your edit, however: so far as I can tell, you were never over the voting limit; I've gotta assume this is some sort of craziness involving voting right around the date rollover. – Shog9 Sep 25 '12 at 3:38
  • @Shog9: I've got a feeling that the new review system was involved; if I vote on a post and advance to the next item too quickly, it might not have recorded the vote count correctly, causing erroneous messages. The system had apparently claimed that I had more votes left than I thought I had, and this appears to have been triggered by the networking issues I mentioned. I'm not sure precisely what went wrong, though, and it could be little more than a simple UI bug... – bwDraco Sep 25 '12 at 3:46
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    By the time you advance in the review queue, your vote should've already been recorded or at very least submitted. Not saying there can't be some UI weirdness there, but it should be as safe as any other way of voting. BTW: it looks like Mechanical snail got the right answer for why 41 votes showed up on your user drop-down. – Shog9 Sep 25 '12 at 4:18
  • big deal. I once had dozen of "race conditions" like this – gnat Sep 25 '12 at 8:19

Another possibility is that it's the same phenomenon as How does someone get to cast more than 40 votes in a day?. That is, one of your votes was on a subsequently-deleted post.

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    This appears to have been the case after all - one of the first answers he voted on yesterday was deleted shortly afterwards. – Shog9 Sep 25 '12 at 4:17
  • I have decided to cast the first vote to close. (Users with at least 250 reputation can view close votes and vote to close on their own questions.) – bwDraco Sep 25 '12 at 14:55

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