[tor-bugs] #24228 [Core Tor/Tor]: Tor keeps on creating new circuits even when it's idle

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#24228: Tor keeps on creating new circuits even when it's idle
-------------------------------------------------+-------------------------
 Reporter:  asn                                  |          Owner:  (none)
     Type:  defect                               |         Status:  new
 Priority:  Very High                            |      Milestone:  Tor:
                                                 |  0.3.2.x-final
Component:  Core Tor/Tor                         |        Version:
 Severity:  Normal                               |     Resolution:
 Keywords:  tor-circuit, regression,             |  Actual Points:
  backport-031                                   |
Parent ID:                                       |         Points:
 Reviewer:                                       |        Sponsor:
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Comment (by dgoulet):

 Continuing to dig here on why, this comes from #16861 (parent of #17592)
 and the changes file (changes/bug17592) reads:

 {{{
 +   - Increase the intial circuit build timeout testing frequency, to help
 +     ensure that ReducedConnectionPadding clients finish learning a
 timeout
 +     before their orconn would expire. The initial testing rate was set
 back
 +     in the days of TAP and before the Tor Browser updater, when we had
 to be
 +     much more careful about new clients making lots of circuits. With
 this
 +     change, a circuit build time is learned in about 15-20 minutes,
 instead
 +     of ~100-120 minutes.
 }}}

 Originally the timeout was 10 minutes:

 {{{
 +#define IDLE_TIMEOUT_WHILE_LEARNING (1*60)
 -#define IDLE_TIMEOUT_WHILE_LEARNING (10*60)
 }}}

 Thus it seems that it *is* the intended behavior here. Are we sure about
 this? CBT will be happy after 15-20 minutes but at the cost of opening
 100+ circuits when a fresh client starts up?

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/24228#comment:7>
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