[tor-bugs] #27356 [Metrics/ExoneraTor]: Reduce database size and variance of query response times

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#27356: Reduce database size and variance of query response times
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 Reporter:  karsten             |          Owner:  metrics-team
     Type:  enhancement         |         Status:  closed
 Priority:  High                |      Milestone:
Component:  Metrics/ExoneraTor  |        Version:
 Severity:  Normal              |     Resolution:  fixed
 Keywords:                      |  Actual Points:
Parent ID:                      |         Points:
 Reviewer:  irl                 |        Sponsor:
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Comment (by karsten):

 irl asked me today how this change improved query times. Here are some
 quick statistics based on log statements over roughly one 1.5 weeks saying
 how much time passed between opening a connection and returning it:

 ||='''Statistic''' =||= '''Before change'''=||= '''After change'''=||
 ||Min. || 37|| 2068||
 ||1st Qu. || 170|| 2173||
 ||Median || 191|| 2197||
 ||Mean || 18912|| 2275||
 ||3rd Qu. || 260|| 2235||
 ||Max. || 3008467|| 17136||

 Despite the increase in minimum, first quartile, median, and even third
 quartile, I'd say that the decrease in mean and in particular maximum
 values make this change a huge improvement. While it's cool that some or
 even most responses in the old approach were really fast, it was the very
 high response times that made the service hard to predict. With the new
 approach, users can expect a request to return within a few seconds.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/27356#comment:18>
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