Opened 8 years ago

Last modified 2 months ago

#4709 new enhancement

Implement bwauth cap for TCP socket exhaustion

Reported by: mikeperry Owned by:
Priority: Medium Milestone: sbws: unspecified
Component: Core Tor/sbws Version:
Severity: Normal Keywords: performance
Cc: Actual Points:
Parent ID: Points:
Reviewer: Sponsor:

Description

Step 0 is to determine if any of the Gbit+ tor relays (especially Guard+Exit nodes) ever come close to running out of TCP sockets.

Step 1 is find some way to measure stream failures from the bwauths, compute a stream_error value, and use it. See #4708 for more details on that.

Child Tickets

Change History (9)

comment:1 Changed 8 years ago by mikeperry

We are seeing some instances of potential socket exhaustion on Moritz's nodes, but it looks like #4710 is going to block implementing detection properly. It also seems to be a very ephemeral and transient condition for his nodes. Most of the time they operate with only ~8-10K connections per interface.

comment:2 Changed 8 years ago by mikeperry

Potential server-side workaround:
http://www.lakitu.us/2011/04/linux-kernel-scaling-ports-and-port-cycling/

Potential code workaround (seems to require kernel and/or libevent patch?):
http://aleccolocco.blogspot.com/2008/11/ephemeral-ports-problem-and-solution.html

comment:3 Changed 8 years ago by mikeperry

Keywords: performance added

comment:4 Changed 7 years ago by mikeperry

Owner: changed from mikeperry to aagbsn
Priority: normalmajor
Status: newassigned

comment:5 Changed 22 months ago by teor

Parent ID: #13630
Severity: Normal

This is a feature that belongs in the new bwauth replacement project, see #13630.

comment:6 Changed 22 months ago by teor

Priority: HighMedium

Priorities and Severities in torflow are meaningless, setting them all to Medium/Normal.

comment:7 Changed 22 months ago by teor

Owner: aagbsn deleted

aagbsn was the default owner, unassigning

comment:8 Changed 21 months ago by teor

Status: assignednew

Mark all tickets that are assigned to nobody as "new".

comment:9 Changed 2 months ago by teor

Component: Core Tor/TorflowCore Tor/sbws
Milestone: sbws: unspecified
Parent ID: #13630

If we do this, it will be in sbws

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