Positions count fell 30% after upgrading to 2.0 beta


#1

Hi,

I upgraded to 2.0 last weekend and since my reception is about 20% lower than with previous version (from 105k down to 70k). I am using dump1090 mutability version. Is this expected? Should I revert to fa dump version? did I miss an update for the mutability package?

Regards,


#2

There were no changes to the decoding side in 2.0, it was piaware only.
Do you have local stats showing a drop in received messages, or is it only the position reports as seen on the FA website that have dropped?
Also check that dump1090-mutability is, in fact, still running and you didn’t revert to some other dump1090 version on upgrade/restart


#3

The piaware health messages seem to indicate that you’re running dump1090-mutability but using faup1090 to translate to the FlightAware format - is that right?
There were some changes to the rules that faup1090 uses to decide when to forward traffic, so that very stale positions are not forwarded - that might be the cause of the reduced position rate (actually, it’s just not sending useless data any more)


#4

I also see a drop in positions reported but NOT in the number of planes reported. This makes sense if it is no longer reporting so called stale positions.


#5

Hi,



  PID USER      PR  NI  VIRT  RES  SHR S  %CPU %MEM    TIME+  COMMAND
29548 dump1090  15  -5 17904 9132 1924 R  34.8  2.0  21858:30 dump1090-mutabi
18295 mlat      25   5 12448 9684 5780 S   2.6  2.2   2431:16 mlat-client
 4857 root      20   0 11196 8692 4440 S   2.3  2.0  35:21.83 fa-mlat-client


I am running fa-up for some obscure reason I forgot. when I started with mutab there was an issue and you (or maybe someone else usggested to use fa-up).

I am now running both m-lat clients, but there have quite alow impact so I would not expect this to be the reason for the drop in my reports.

I will try to recconfigure dump-mutab to respond to fa without going through FAdump.


#6

Better to stick with what you have - the drop in position count is cosmetic, the faup1090 change is there for a reason…

(I will roll that change or something similar into dump1090-mutability soon too)


#7

Hi All,

Thanks for the feedback. I eventually when up in the attic the day before last night, to check on the antenna, and found out that the antenna had slept down the PVC tube. I have pushed it all the way up the tube, and I am back in the 100k positions per day.

FWIW, this confirms that 1/2 length part of coco antenna out of the attic bring 20% more positions than the whole antenna in the attic.

Next step rebuild a coco and mount it fully out.

++