Opened 8 years ago

Closed 8 years ago

Last modified 7 years ago

#4294 closed enhancement (fixed)

Add percentiles of bridge descriptor downloads by fingerprint to served-descs-stats

Reported by: karsten Owned by: Sebastian
Priority: Medium Milestone:
Component: Core Tor/Tor Version:
Severity: Keywords: tor-relay
Cc: Actual Points:
Parent ID: Points:
Reviewer: Sponsor:


Sebastian and I discussed Tonga's statistics about served bridge descriptors:

served-descs-stats-end 2011-10-23 23:03:31 (86400 s) total=515010 unique=3766

We suspect that Tonga also serves and counts relay descriptors here. There are only 1665 unique bridge fingerprints in descriptors published since 2011-10-20, so these can't just be bridge descriptors. Also, the total number of 515K descriptor fetches is much higher than expected.

Sebastian works on a patch to exclude fetches for relay descriptors to only count bridge descriptors. But we wonder if two numbers are enough to explain what's going on.

I suggest to include a few percentiles of downloaded descriptors per unique bridge fingerprint in the statistics. The output could be (example data):

served-descs-stats-end 2011-10-23 23:03:31 (86400 s) total=515010 unique=3766 max=12095 q3=1752 md=498 q1=112 min=5

There are two necessary changes to the implementation:

  1. The digestmap needs to store a pointer to an integer counting the downloaded descriptors by bridge fingerprint.
  1. When formatting the server descriptor stats, we need to add all counters to a (smart?)list, sort the list, and write list[0], list[length/4], list[length/2], list[3*length/4], and list[length-1] to the output string.

Child Tickets

Change History (6)

comment:1 Changed 8 years ago by Sebastian

Status: newneeds_review

Implemented in ticket4294 in my repository. A bit of review would be nice, I want to give this to Lucky soon to run on Tonga.

comment:2 Changed 8 years ago by nickm

Looks ok. Let me suggest an additional change to make it more efficient... have a look at ticket4294 in my public repository.

comment:3 Changed 8 years ago by Sebastian

pushed a fixup commit to ticket2494

comment:4 Changed 8 years ago by nickm

Resolution: fixed
Status: needs_reviewclosed


comment:5 Changed 7 years ago by nickm

Keywords: tor-relay added

comment:6 Changed 7 years ago by nickm

Component: Tor RelayTor
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