[tor-bugs] #2550 [Torflow]: bwauth should reschedule quicker bandwidth test when bandwidthrate changes?

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#2550: bwauth should reschedule quicker bandwidth test when bandwidthrate changes?
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 Reporter:  arma         |          Owner:  mikeperry
     Type:  enhancement  |         Status:  new      
 Priority:  normal       |      Milestone:           
Component:  Torflow      |        Version:           
 Keywords:               |         Parent:           
   Points:  ?            |   Actualpoints:           
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Comment(by arma):

 Replying to [comment:4 mikeperry]:
 > Option 2 is technically what we already do now: We use the previous
 consensus descriptor value to multiply the measured ratio against. It is
 possible this is not optimal because we don't fetch often enough, and need
 to set torrc options FetchDirInfoExtraEarly and FetchDirInfoEarly.
 >
 > It is also possible that we are actually measuring a low ratio on some
 bw auths and a high ratio on others, just based on when we measure.
 Depending on if the relay is actually rate limiting, or just altering
 MaxAdvertisedBandwidth, the ratio we get could be either super low while
 the relay reports a low value, or super high...

 I meant something different by 'the ratio' than I think you do.

 I meant the ratio of that relay's new capacity to its old capacity.

 I think you mean the ratio of the performance we see from that relay
 compared to its peers (who advertise the same capacity).

 So in my option 2, if the relay moves from 1000MB-but-we'd-advertise-
 3000MB to 100KB, then we advertise 300KB. It's quite a hack I admit.

 > Option 3 is unlikely to work out if the bandwidthrate change is too
 frequent.. We are not likely to gather measurements for all values.

 No, option 3 is might work ok if the change is frequent. It will fail if
 the bandwidthrate changes to too many different values.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/2550#comment:8>
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