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View Counting at Reddit

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61–70 of 121 posts

Re: View Counting at Reddit

#61
post #52
post #48

So how do they determine whether a user has viewed a post already? I would think that unique counting is accomplished using the hyperloglog counter, but the article says that this decision is made by the Nazar system, which doesn't use the hyperloglog counter in Redis.

Thats true, I am thinking that Nazar is more like spam filter and monitors the user behavior.

Pretty much, yeah.

Re: View Counting at Reddit

#62

Wouldn't it had been easier to simply increment a counter for each visit and then set a short lived cookie in the browser for that post? And put the spam detection system before the counter increment

Yes, that was my idea as well. They must have some sort of cache system for serving basic user meta-data at scale when a page is loaded, and they could add a time-expiring list post ids of the posts viewed by a user to do detection on a per user basis on the backend.

I think they want to break it into different services for (whatever) reasons.

Running a counter across a sharded in memory cache implementation (like Redis) for something like post views should be ok, but they might have some weird rule-sets for spam detection that are slow.

Re: View Counting at Reddit

#63
post #11

Earlier quoted context omitted.

Traditional forum style sorting just sorts for controversiality. Posts that generate heated discussion will continue to push their way to the top. This is okay but it means that non controversial stories will not make it to the top, which is honestly one of the largest benefits of news aggregator sites.

How about, here and on reddit, being able to mark threads you're interested in, and having a page where you can see those sorted by last reply. On HN, make that page refresh every 15 or 60 minutes or whatever. Heck, once every 24 hours would be enough... sometimes I just want to talk about the things that interest me, with the people that are interested in them. I would love to be able to think on something for a few…

> As they are now, reddit and HN are require you to be there when something is "current", and that's ultimately not that much better than TV.

One thing I don't think people have addressed is that that's the goal for them; it's not necessarily to be "useful" to the end user. If they can make users feel like they have to be on reddit 24/7 to stay "current" and not miss anything, then they will. Facebook does the same thing.

Re: View Counting at Reddit

#64
post #48

So how do they determine whether a user has viewed a post already? I would think that unique counting is accomplished using the hyperloglog counter, but the article says that this decision is made by the Nazar system, which doesn't use the hyperloglog counter in Redis.

Why can't they just associate a list of viewed posts with each user, or list of users that viewed a post with each post, and check that? I don't get why this needs any consideration.

Re: View Counting at Reddit

#65
"We want to better communicate the scale of Reddit to our users."

If that's true why did they hide vote numbers on comments and posts? It used to say "xxx upvotes xxx downvotes" now it just gives a number and hides that.

Re: View Counting at Reddit

#66
post #65

"We want to better communicate the scale of Reddit to our users." If that's true why did they hide vote numbers on comments and posts? It used to say "xxx upvotes xxx downvotes" now it just gives a number and hides that.

It's to deter bots. The numbers weren't previously accurate, they were fuzzed (also to deter bots).

https://www.reddit.com/wiki/faq#wiki_how_is_a_submission.27s...

Re: View Counting at Reddit

#67
post #34

Earlier quoted context omitted.

Funnily, reddits vote fuzzing is entirely useless. They always fuzz equally relative to the actual score. So, instead of monitoring once from another browser, you monitor from 100 browsers, and calculate the average before and after your bot votes.

Ok but multiplying a spammer's cost by 100 (or 3) isn't useless.

But you're multiplying it by some number for every single comment/reply. Spammers work through large numbers... make each one a little bit harder, and it adds up.

Re: View Counting at Reddit

#68
post #48

So how do they determine whether a user has viewed a post already? I would think that unique counting is accomplished using the hyperloglog counter, but the article says that this decision is made by the Nazar system, which doesn't use the hyperloglog counter in Redis.

Why can't they just associate a list of viewed posts with each user, or list of users that viewed a post with each post, and check that? I don't get why this needs any consideration.

Have you stopped to think how many users that is and how many posts?

Viewing a single thread could require five hundred associations.

Re: View Counting at Reddit

#69
post #66
post #65

"We want to better communicate the scale of Reddit to our users." If that's true why did they hide vote numbers on comments and posts? It used to say "xxx upvotes xxx downvotes" now it just gives a number and hides that.

It's to deter bots. The numbers weren't previously accurate, they were fuzzed (also to deter bots). https://www.reddit.com/wiki/faq#wiki_how_is_a_submission.27s...

I don't quite see the connection. How exactly does this deter bots?

Re: View Counting at Reddit

#70
post #69
post #66

Earlier quoted context omitted.

It's to deter bots. The numbers weren't previously accurate, they were fuzzed (also to deter bots). https://www.reddit.com/wiki/faq#wiki_how_is_a_submission.27s...

I don't quite see the connection. How exactly does this deter bots?

It's difficult to see if their votes are counting, allowing Reddit to silently-ignore their votes without them knowing.
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