Explain why a relay is an 'almost-fast-exit' and not a 'fast-exit'

[gsathya]

We should provide more information on why a relay is in the 'almost-fast-exit' and not a 'fast-exit'. This will help relay operators check their relay status and hopefully correct it and make it a 'fast-exit'.

Maybe we should provide this info when someone clicks on a relay when filtering by 'almost-fast-exit'?

[karsten]

Sounds useful. Where would you add that info, that is, what do you mean by "when someone clicks on a relay"?

[arma]

I agree that it would be useful

[gsathya]

Replying to karsten:

Sounds useful. Where would you add that info, that is, what do you mean by "when someone clicks on a relay"?

Make the entire row "clickable" like ​http://twitter.github.com/bootstrap/javascript.html#collapse or just use popovers. This feature will require changes in compass.py

[karsten]

So, we need to solve two problems here: add fast exit information to compass.py and display that information nicely on the website.

For extending compass.py, I could imagine adding a new flag --display-fast-exit-info that adds four new columns to the output:

• bw_rate_mbits would contain the bandwidth rate in MBit/s,
• adv_bw_kbytes would contain the advertised bandwidth in KB/s,
• exit_ports would list relevant permitted exit ports, e.g., 80/443/554, and
• same_24_id would list the relay's position in the top-N list of fast exits by exit probability if the relay meets the "fast exits, any network" requirements, or N/A if it doesn't meet those requirements.

These four new columns would be added anywhere before the "Autonomous System" column, which is the only column with previously undefined length. Or these columns could be appended as new last columns if the maximum column width of "Autonomous System" can be determined from the table elements before writing the table header.

For displaying the new information on the website, there could be a new column "Fast exit" after the "Guard" column with values "Yes", "Almost", and "No", that has additional information in popovers. The popovers would then summarize why a relay is only in the "Almost" or "No" category by looking at the four new columns.

Alternatively, we could add a new column fast_exit instead of the four columns suggested above that contains a full sentence summarizing whether a relay is a fast exit, e.g., "Almost. Bandwidth rate is only 85 Mbit/s and exit ports only contain 80/443." The tricky part there would be to display that sentence in the command-line output of compass.py which uses fixed-length columns. That's the same problem as for determining how long the "Autonomous System" column is supposed to be.

All in all, this change requires a lot of new code. Probably more than it seems from a user perspective.

[karsten]

Capitalize summary.

[irl]

The metrics team has put a goal of shutting down Compass in its roadmap and merging functionality with Relay Search (previously known as Atlas). This ticket is specific to Compass and as development on Compass has ceased, I am marking this ticket as wontfix.

See #23517 for information on the planned work to integrate Compass functionality into Relay Search.