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Sliding Window with Counters

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#1

Hi team,

Sliding Window with counters example, the requests are counted and stored with the time stamp. How will this solve fixed window problem ? Consider the drawback of fixed window approach, sliding window with counters will also have the same problem.

please correct me if my understanding is wrong.

Thanks,
V

#2

I think what author is trying to say for example in fixed window imagine 5 request per 10 seconds

1 second --- 1 request 
.
.
.
6 second - 2nd request 
7 second - 3rd
8 second - 4th
9 second - 5th
--
11th

Here on 11th second it will check the the user startime of was 1 second for 1st request which is past 10 second then it will reset to 1 conter and will allow . Now in this situation what if 11th 12th 13 and till 15ht second you get request. If you see that from 6th second to 15th second you got more than 5 request.
ā€¦
In sliding window

user 1 : 1s,6s,7s,8s,9,s
when on 11th second comes it will remove from queue all request which is < current - 10sā€¦ so you will still have 6s,7s,8s,9s in queue which is >= 5 request in that case it wont allow.

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#3

I think this is explained for sliding window, not sliding window with counters.

#4

It seems that sliding window with counters still has the problem at the minute level. But at the hour level, it does not.

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