[tor-bugs] #22255 [Core Tor/Tor]: Frequent OOM kills of tor process

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#22255: Frequent OOM kills of tor process
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 Reporter:  DeS           |          Owner:  (none)
     Type:  defect        |         Status:  closed
 Priority:  High          |      Milestone:  Tor: 0.3.0.x-final
Component:  Core Tor/Tor  |        Version:
 Severity:  Major         |     Resolution:  fixed
 Keywords:                |  Actual Points:
Parent ID:                |         Points:
 Reviewer:                |        Sponsor:
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Comment (by teor):

 Replying to [comment:80 starlight]:
 > Replying to [comment:79 teor]:
 > > I'd still like to see someone repeat this analysis with 0.3.2.8-rc,
 and post the results to #24737.
 > > It's going to be hard for us to close that ticket without any idea of
 the effect of our changes.
 >
 > I'm not willing to run a newer version till one is declared LTS, but can
 say that even when my relay is not under attack memory consumption goes to
 1.5G with the 1G max queue setting.  Seems to me the 2x max queues memory
 consumption is a function of the overheads associated with tor daemon
 queues and related processing, including malloc slack space.
 >
 > Anyone running a busy relay on an older/slower system and with
 MaxMemInQueues=1024MB can check /proc/<pid>/status to see how much memory
 is consumed.  Be sure DisableAllSwap=1 is set and the queue limit is not
 higher since the point is to observe actual memory consumed relative to a
 limit likely to be approached under normal operation.
 >
 > Another idea is to add an option to the daemon to cause queue memory
 preallocation.  This would be a nice hardening feature as it will reduce
 malloc() calls issued under stress, and of course would allow more
 accurate estimates of worst-case memory consumption.  If OOM strikes with
 preallocated queues that would indicate memory leakage.

 I have answered this on #24737, because it will get lost on a closed
 ticket.
 Please move all future discussion there.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/22255#comment:82>
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