[fixed] Large track slows app until unusable

[twoten]

If I create a track for a few hours AlpineQuest runs so slow it can't be used. I get an error message that says:

"Sorry
Activity AlpineQuest (in application AlpineQues GPS Hiking) is not responding".

It then gives the option to force close or wait. If I select wait I get the message reappear.

A couple of times I have problems stopping he track recording and the .GPS file corrupted. If I can manage to stop recording the track which takes quite a long time and several messages later the app starts to respond quicker.

The last .GPX file I recorded and had a problem with was 354.7KB in size and contained 2 tracks
1) 327 Waypoints 1 Segment 18.57 Min's
2) 2776 Waypoints 1 segment 3.45 hrs.


As it is at the moment I couldn't rely on the tracking of this app if I went on a day or even half a days hike.

[Psyberia-Support]

Hi,
I think you begin to reach the limit of the applications.

There are some limitations when recording large tracks:
- The low memory on phones (only few MB / per app) which can lead OutOfMemory crashes, and AlpineQuest needs to keep all locations in memory;
- The fact that AlpineQuest needs to draw all points of the track (for example when sliding the map), which can be long if there are hundred of locations;
- The fact that AlpineQuest auto-saves the track file every 30 new locations, and the SD write speed is not so fast. It freezes the application when the file is being saved, and for files >100KB, it becomes visible.

The file is also saved when stopping the track record, that's why it can take a long time in this case.

The problem is that the memory, the SD write speed, the CPU speed, etc. depends on the phone, and can be very different. It is difficult to warn the user correctly depending on its device.

What I can do:
- Optimize the memory usage for tracks.
- Optimize the redraw of tracks, maybe by limiting the number of drawn locations.
- Reduce the auto-writes. Maybe saving the file every 100 locations is enough.

What you should do:
- When you plan to record long trips, reduce the sec/fix value. I usually use 10sec/fix (=360 locations / hour) for few hour tracks, but for longer ones maybe less fixes can be good.

Regards

[twoten]

I had guessed the problem was caused by screen redraw and processor usage when saving, as the file gets to a certain size it takes longer to save a file and this in turn uses more processing power for longer.

Up to now I have been using 'My Tracks' to record tracks which works extremely well, I can record a rack for over 8 hours and it doesn't appear to have a negative affect on the phone (except battery) or app.

The 'My Tracks' settings I use are:

• Track not split

• minimum time between points is set to highest which is less than 2 seconds

• Minimum distance between points I have set to 6 ft but the recommended is 16 ft MAx

• Distance between points is 656 ft

• Signal sampling frequency is off.

Is there something here that would improve the performance of track recording in AlpineQuest or is it the way the app is optimised?

Something that may be useful for other users, if they find the app forces close or the track doesn't finish recording and the file can't be read it is worth trying to append the file in question and then stop recording, I have found this finalises the track and allows it to be viewed.

[Psyberia-Support]

Distance between points is 656 ft

I didn't really understand this setting. What's the difference between this other setting: "Minimum distance between points I have set to 6 ft but the recommended is 16 ft MAx".

If the distance between 2 points is really 656 ft, this could explain why such long tracks can be recorded.

I never used My Tracks during hikes, so I can't compare track capabilities. But as far as I understand how it works, it seems to record locations in an optimized way. This is better for performances, but you need to manually export your tracks in a standard format. AlpineQuest stores directly the tracks in GPX files, which is not optimized for adding locations (need to rewrite all the file).

What you can do right now is to reduce the frequency of waypoints recording. In the geolocation settings, you can reduce the number of waypoints / hours. For exemple, if you plan to record a track for lot of hours, you should use something like 300 locations / hours.

I'll record long tracks with both apps, and make comparisons. I really hope AlpineQuest will be able to perform My Tracks soon

[twoten]

Distance between points is 656 ft

I didn't really understand this setting. What's the difference between this other setting: "Minimum distance between points I have set to 6 ft but the recommended is 16 ft MAx".

I didn't make that very clear, the 656 ft is the Maximum distance between points, if the two points are further than this the track will be split.