Android Sometimes Loses Sync When Changing Networks

[JimmyTheSaint]

Generally speaking, the Android app is pretty reliable, and I've only experienced problems intermittently. The PostDownload problem is discussed in another thread, but another problem that also crops up maybe once a week is the sudden, inexplicable loss of sync. No clue how to troubleshoot it, but after some months of experience, it seems to only ever lose sync when changing networks. Most times, changing networks isn't a problem, so being intermittent makes it difficult to guess what's going wrong.  For example, I move from my 3G data plan back to home WiFi LAN, and now I think even when staying on 3G moving from one area of the city to another. All my other devices stay in sync, including my laptop that travels with me, sometimes tethering to 3G, sometimes logging into various WiFi networks.

 

The fix is usually to open the BitTorrent Sync app, and then it will start to sync. At those times, all the folders first say "0 devices online." When I open the app while there's no problem, it will often say "n devices online" even though I have auto-sleep on, as if to indicate sync isn't lost. But other times, it will still say "0 devices online" although sync isn't lost. I really don't know any other way to get feedback from the app as to its status. But as far as I can tell, whenever I discover sync has been lost, my S4 has recently moved networks. My Note 2 is my backup, and it hasn't left my home WiFi in months, and has never lost sync. Maybe other people have observed the same pattern associated with changing networks. Also, any suggestions how to prevent losing sync are welcome. My current solution is to turn off my S4's WiFi, and use 3G even at home.

[dms2013]

I have the same issue. When I reboot my computer, the connection is lost until it's back on and BTSync running.

Sent from my Nexus 4 using Tapatalk

[JimmyTheSaint]

I have the same issue. When I reboot my computer, the connection is lost until it's back on and BTSync running.

Sent from my Nexus 4 using Tapatalk

 

By "computer," am I correct that you don't mean Android? Also, you're saying that you don't have sync while until BTSync is running, but that sounds normal. What am I missing here?

 

But I must thank you for your signature. I had no idea they finally provided Tapatalk access to these forums.

[StNick]

I have the same problem as described in the OP.  However, my conclusion was that it was not the change of networks to blame, rather a quirk of Android whereby the OS automatically kills apps that are not in use.  Many other apps that I use have had to deal with this issue in the past and usually what they do is include a "always keep in memory" option.  I can't say for sure what is actually happening in the background, but ultimately the result is that Android doesn't kill the process when this option is ticked.

 

Perhaps when you are away from home for an extended period of time using 3G data, and you have told BTSync not to use cellular data, the app is essentially dormant, and that's when Android steps in and kills the process to free up memory for another app.  Whereas when you're on a LAN, the app is polling constantly, thereby keeping the app "alive" and Android doesn't interfere.

 

Hopefully Bittorrent come up with a solution because right now, I simply cannot trust that BTSync is doing what it is supposed to be doing and I have to remember to load it up manually every now and then just to be sure.

[JimmyTheSaint]

Perhaps when you are away from home for an extended period of time using 3G data, and you have told BTSync not to use cellular data, the app is essentially dormant, and that's when Android steps in and kills the process to free up memory for another app.  Whereas when you're on a LAN, the app is polling constantly, thereby keeping the app "alive" and Android doesn't interfere.

 

My BitTorrent Sync is always on, 3G or WiFi. That's not to say the Android system couldn't come along and kill it anyway. Its notification never leaves my status bar, but that's also no guarantee against the system killer. But you'd think that since the app wakes up every 30 minutes, then such activity would prevent it getting killed. I've also raised the process's priority as high as possible by renicing it to the lowest possible value, but apparently that doesn't make a difference, either. Next time I catch it sleeping, I'll make sure to check on it in my third party task manager. But it shows the BTSync app only uses about 40MB of my 2GB of memory, which is about the same as other apps that never get unloaded from memory. So I'm skeptical that the app gets killed.

[StNick]

Hmmm...  Then I'm afraid I'm a bit clueless.

 

My wife's phone doesn't seem to exhibit the same problem that you and I are having.  I installed BTSync on her device about three weeks ago, and I am quite sure that she hasn't so much as rebooted, let alone started the app up manually.  However, her files are still syncing just fine.

 

Perhaps it is something to do with Jelly Bean and above, and how it manages processes.  I see you're running 4.2.2, and I'm on 4.4.2.  Would be nice if we could get a few more test-cases to drum up some noise about the issue.