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Subject:Wishlist - reliability 

shchenka

7:56
Monday
4-May-2009

Hi Stephen, you know how much I love TMJ, packed with all the features, and how I appreciate all the new features and improvements. I'm always thrilled to download and try a new version to see what new functions will surprise me.

I would however like to suggest that one area in which it could be further improved is the stability. This has been already improved a lot, but still. I'm sure you'll appreciate how annoying it can be to loose your long recorded track only because the phone battery went flat. Loosing track or waypoints is especially frustrating when you're travelling abroad and using tmj-mobile in the "offline mode", because of the connection costs.

I know that in reality we can not always expect a clean app shutdown, as this may depend a lot on the behaviour of the host operating system on the mobile. Also, physical things can happen to the phone as the handset dropped on the floor, battery disconneted etc.

But maybe some improvements could be done to allow the tmj to recover gracefully after a disaster. Like automated backups of configuration/waypoints/track to alternate files ?

I expect the two major causes of the problems could be files open for writing while the application get killed (which may leave the files corrupt upon restart), and data in memory not stored permanently (which could lead to data loss).

Any thoughts here ?

Cheers,

--shchenka
 

Stephen

22:04
Monday
4-May-2009

Location:
Surrey, UK

Phone Model:
BB 9800 Torch
BlackBerry 8900
SE W910i
Nokia 5800

Hi Shchenka,

Sorry to hear you're still getting the same old problems with TMJ losing data. Although this has only very occasionally happened to me, I know how frustrating it is when it does happen!!

Its a difficult one to solve though, since this sort of instability often boils down to an individual phone model or manufacturer, so its difficult to troubleshoot without having access to that particular model (are you still using the Nokia N95, by the way?). As you're no doubt aware I've mostly developed TMJ using Sony Ericsson phones, so its perhaps a little better tuned to running on them, and I'm currently trying to improve BlackBerry support, so admittedly Nokia has got put slightly to one side!

When TMJ crashes is it usually due to an obvious 'external' cause, like as you say being dropped, battery dying, etc. Or will it just die of its own accord? (Incidentally, do others reading this experience similar issues?)

When it does crash, how much of the data is lost? Is it:
- the last few trackpoints/recently added waypoints (least annoying)
- the whole track, but old waypoints survive
- the whole track, all waypoints
- Simple settings - Menu tickboxes etc, eg Plan Menu/View Options/Show Scale
- Is previous Lat/Long retained or does this revert to 0,0
- More persistent settings, in particular Menu/Settings/Other Settings/TMJ Device code, etc
- Everything
- Everything, and program is no longer installed - ie you have to reinstall from the JAR file (worst option!!)

Do you use the GPS/Logging/Log to GPX file option? Does this file disappear as well?

Do the Menu/Settings/Debug Options/Save & Backup Settings and Restore Settings options do any good?

All of the TMJ Settings/Track/Waypoints etc are stored in J2ME RecordStore() objects, which are handled by the phone OS/JVM. There are separate RecordStores for each item type (Track, Route, Waypoints...), with two separate ones for the Settings (Simple settings and Persistent settings). (Incidentally I'm planning to revise these last two for the next version, which may help if you're generally getting partial rather than total data loss)

The Save & Backup Settings option saves the settings to duplicate RecordStores, which aren't then touched until another backup or restore is done. So if these duplicate stores aren't surviving the crash either, then it suggests that the entire J2ME RecordStore system is being corrupted (which really has to be down to the OS). You mention automating a backup to a file, but the trouble then is that you'll end up getting loads of Permission Prompts popping up each time it does the backup. (And if you miss a prompt, then the entire program will hang until the prompt is accepted/rejected).

One possibility with the log file could be a shortcut option to close the current log file and start a fresh one (hopefully leaving the previous file high-and-dry on the memory card). Could that be of use? I guess ideally this might happen automatically (say every 30 minutes or whatever) but again because of the security prompts this isn't really feasible.

Will ponder it some more...

Cheers,
Stephen
 

macpanda

19:22
Wednesday
6-May-2009

Location:
Nailsea, North Somerset, UK

Phone Model:
Nokia N95
Sony Ericsson C905

I have 2 experiences with this using a Nokia N95.

A week or so back I was mis behaving with proximity alerts, and couldn't stop the phone telling me I was near home. (in fairness I was near home) but I had to turn off the phone and lost all my settings. Worse, the phone refused to save them again (no error, just didn't save). I uninstalled, reinstalled and all OK.

Last weekend I was off cycling and after 3 1/2 hours the battery died. It warned me so again entirely my fault, but the phone died. When I changed the battery (it's a Nokia, you carry a spare) it happily carried on tracking from where it left off (GPX log) and no data was lost.
 

Stephen

20:05
Thursday
7-May-2009

Location:
Surrey, UK

Phone Model:
BB 9800 Torch
BlackBerry 8900
SE W910i
Nokia 5800

Mmmm, I wonder if the proximity alerts stuff is part of the problem (it does use extra memory and processing calculations so might have an effect, especially if you've got lots of waypoints). I actually rarely use these myself so maybe I need to look into this a bit more...

Glad to hear that the battery dying didn't cause a problem though!
 

shchenka

23:48
Thursday
28-May-2009

Hmm, I've tried to reproduce it but ... maybe I've finally learnt to be cautious enough with other applications ?
So far I had not seen a single crash since my first post in this thread ... :)
 

Stephen

7:45
Friday
29-May-2009

Location:
Surrey, UK

Phone Model:
BB 9800 Torch
BlackBerry 8900
SE W910i
Nokia 5800

I guess I'll take that as a minor sign that TMJ might not be the root of the problem!! Glad to hear its been behaving a bit better - hopefully we've not spoken too soon... ;-)

Cheers,
Stephen
 

shchenka

8:12
Tuesday
16-Jun-2009

Probably it's not the TMJ's fault. I think in my case is just the poor multitasking handling of the OS on the N95 (it just happened again). This really happens when I'm careless enough to use other apps together with the TMJ, notably the web browser or the camera.

On the other hand - this only happens to TMJ, other applications are intact.

TMJ's crashing is a minor problem to me - what bothers me is th loss of data/configuration in such a crash.

I would be happy to be able to manually restore the configuration and waypoints (and if possible track, too) after a crash. Do you think it would be possible to store a copy of the TMJ's configuration in an external file on the mobile and then to be able to restore it ?
That same mechanism could be then used when upgrading TMJ to a newer version (I cant remember if it keeps the old configuration but I think it did not in the past). Having to manually configure all the options again and again through the ui is quite tedious, especially if you're doing this in the field where I'd rather use the time for other activities.

For the waypoints I'm using export/import to OZI and it seems to do the job :)
 

Stephen

9:41
Wednesday
17-Jun-2009

Location:
Surrey, UK

Phone Model:
BB 9800 Torch
BlackBerry 8900
SE W910i
Nokia 5800

Hi Shchenka,

I've added a Settings Backup/Restore to File function for the next version, which should help to preserve most of the customised settings (not the track/waypoints though). Not sure if I'll enable it for version upgrades, since these often require alterations to the settings storage format - the next version will need to be freshly installed, for example, but perhaps it will help for more minor upgrades in the future.

I got used to my W910 which preserved settings on upgrading, whereas my BB8900 doesn't, so I've been having to reset all the settings each time I test a new build, often several times a day - very tedious indeed! :-)

Cheers,
Stephen
 
 

shchenka

21:36
Monday
22-Jun-2009

Many thanks Stephen, the upgrades are not a problem (for me ;) - this mostly happens only once for each new version. But being able to manually backup the settings will be of help in the situations that I described.
 

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