Scanners on bwscan+moria sometimes don't make progress

Scanner 3 is still stale.

WARN[Sat Aug 27 22:40:12 2011]:Bandwidth scanner scanner.3 stale. Possible dead bwauthority.py. Timestamp: Wed Aug 24 17:11:27

Note the bwscan vm is running sqlalchemy 0.5.6 still. Perhaps we should just upgrade to 0.7.1 and restart?

added component::core tor/torflow in Legacy / Trac owner::aagbsn in Legacy / Trac priority::high in Legacy / Trac resolution::user disappeared in Legacy / Trac status::closed in Legacy / Trac type::defect in Legacy / Trac labels

Upgrading to 0.7.x is probably not a bad idea, but I am confused -- the scanner seems to be making progress: {{ DEBUG[Sat Aug 27 10:45:39 2011]:Starting slice number 3 DEBUG[Sat Aug 27 11:11:49 2011]:Starting slice number 4 DEBUG[Sat Aug 27 12:15:31 2011]:Starting slice number 5 DEBUG[Sat Aug 27 13:19:29 2011]:Starting slice number 6 DEBUG[Sat Aug 27 14:26:42 2011]:Starting slice number 7 DEBUG[Sat Aug 27 15:04:15 2011]:Starting slice number 8 DEBUG[Sat Aug 27 15:36:56 2011]:Starting slice number 9 DEBUG[Sat Aug 27 16:23:38 2011]:Starting slice number 10 DEBUG[Sat Aug 27 16:49:48 2011]:Starting slice number 11 DEBUG[Sat Aug 27 17:47:58 2011]:Starting slice number 12 DEBUG[Sat Aug 27 18:29:50 2011]:Starting slice number 0 DEBUG[Sat Aug 27 19:43:41 2011]:Starting slice number 1 }}

I also checked through the logs and did not see anything unusual (did not appear stalled). Do we have any other theory as to what is happening?

Trac:
Cc: N/A to aagbsn@extc.org

No idea. Possibly it stalled our for a bit and then started going again? I have not gotten any mails lately, and the ones I did get were intermittent.

This could be caused by the new ratio grouping (legacy/trac#3444 (moved)). moria is also not making progress on occasion, despite taking continued measurements and not crashing.

Basically, grouping by ratio may cause higher churn in the slices, since it depends on both measured value and observed value. If the churn rate is faster than slice progress, no progress will be made.

I also flipped FetchDirInfoEarly and FetchDirInfoExtraEarly in c86c1e13. Since they will cause consensus fetches every hour, this may be even worse.

We could make the slices smaller to ensure completion, but I think nothing currently ensures that we will get at least one exit node in a slice. Perhaps we should still make them smaller, and also fix the selection to ensure exits anyway...

Trac:
Cc: aagbsn@extc.org to aagbsn@extc.org, arma
Priority: normal to major

Trac:
Summary: Scanner on bwscan vm is not making progress. to Scanners on bwscan+moria sometimes don't make progress

My cron has stopped mailing me complaints like this. I'm not sure if that means they're still happening and I've stopped being told, or if they magically disappeared.

No clue if the underlying bug was fixed, but anyway the symptom is three years old now. Closing.

Trac:
Status: new to closed
Resolution: N/A to user disappeared

closed

moved from legacy/trac#3835 (moved)

added Bug label and removed 1 deleted label

removed 1 deleted label