Locked Database when scheduling recordings

[W3bbo]

After over 8 years with Beyond TV I have finally made the move to NextPVR to allow support for DVB-T tuners - loving it so far, much easier to configure!

I have one serious issue where if I attempt to schedule a recurring recording from a client whilst other recordings are in progress I get the following SQL error which requires a restart of the recording service to unlock:

The server PC is a clean build of Windows 7 and I have applied the latest patch pack to NextPVR 3.1.1 (both client and server)

Scheduling the same recording when nothing else is being recorded or directly on the server works as expected. Also scheduling a quick recording on the client under the same conditions works fine.

Client and server are connected on a 100Mbps wired LAN.

I have attached the log files from both client and server in a zip file.

Any assistance would be greatly appreciated as this is that last problem holding back family approval of the change!

[Kiwi]

Yes there seems to be a "database locking up" problem with the 3.1.1 release. None of the post 3.1.1 patches address this yet, so will just have to wait patiently for sub to troubleshoot.

Anyway, the locking up seems to be happening when NextPVR has been running sometime, and almost always is caused by editing an existing recurring recording. But I do get it sometimes just by adding a new manual one-time recording. No choice, I just had to reboot the computer to get it working again.

[sub]

Yes there seems to be a "database locking up" problem with the 3.1.1 release. None of the post 3.1.1 patches address this yet, so will just have to wait patiently for sub to troubleshoot.

Anyway, the locking up seems to be happening when NextPVR has been running sometime, and almost always is caused by editing an existing recurring recording. But I do get it sometimes just by adding a new manual one-time recording. No choice, I just had to reboot the computer to get it working again.

I've never seen any database locks like these with 3.1.1. If you can find a reproducible set of steps, let me know and I'll try to duplicate it here. If I can see the problem, then I can also fix it.

[W3bbo]

Hi Sub - It's great to be back with a product that's still under development!

I can reproduce the problem at will by performing the steps in the first post.

In addition, I can reliably reproduce the problem on the server by performing the following:
* Set two programmes recording simultaneously (using quick record from the guide)
* Attempt to schedule a recurring recording (Season - all episodes, keep 10)
* Database lock occurs

The attached logs (first post) are as clean as possible when capturing the problem (shut clients and server down, delete logs, restart, cause problem, take logs). To eliminate any potential OS causes I've also tried disabling AV software and the windows firewall but the problem still remains.

I'm happy to provide any further logs or testing as required to help get to the bottom of the problem or alternatively provide remote access as required.

[gEd]

I've never seen any database locks like these with 3.1.1. If you can find a reproducible set of steps, let me know and I'll try to duplicate it here. If I can see the problem, then I can also fix it.

I uploaded a test case and logs in 2 recent pre-release forums but they didn't generate any response.
http://forums.nextpvr.com/showthread.php...post470250

My perception is that the problem does not reproduce with <EPGLiveTVUpdates> set to false

[W3bbo]

Changed the <EPGLiveTVUpdates> setting on the server and tried to reproduce the problem with no success - I think that's it!

Many thanks gEd, don't think I'd have tracked that down in a hurry. You've got to love SQL locks...

I'll perform more testing tonight to make sure but all is looking good.

[Zeb]

That setting is available on Settings->Misc, so there's no need to edit <EPGLiveTVUpdates> in Config.xml. So these database locks occur even if there hasn't actually been an EPG update during live TV?

[gEd]

from my tests, yes. If I have EPGLiveTVUpdates set True, I can reproduce the problem in 5-10mins just by recording 1 show and then quickly scheduling a bunch of other ones. No EPG update is being done at the time, certainly not one that I have scheduled or triggered.

So with EPGLiveTVUpdates set to true, when NPVR starts an instance of a recording it appears as though it grabs hold of the database at some point (but not immediately) and doesn't release its lock on the db.
perhaps this is a db concurrency issue with the version of the MS database that sub is using (as martin suggested some time ago iirc).

[Kiwi]

I've never seen any database locks like these with 3.1.1. If you can find a reproducible set of steps, let me know and I'll try to duplicate it here. If I can see the problem, then I can also fix it.

Thanks.

Anyway, the setting of the "EPGLiveTVUpdates" flag to false seems to work, I will report back if any new lockups occur.

[W3bbo]

I can confirm that after testing extensively last night that this does indeed fix the problem.

With the EPGLiveTVUpdates enabled, I can reproduce the database lock problem reliably (set one channel recording, then attempt to set a new recurring recording). With the setting disabled I can start recordings on all three tuners, watch recordings on four clients and successfully schedule multiple recurring recordings simultaneously.

Thanks to all for your help and support.