24 replies to this topic

[krister67]

I´ve noticed some small glitches in recorded material since the upgrade to Kernel 3.1.1.
While playing a recording the playback skips approx. one second, this can occur several times.
Never had this problem before using the older kernel.
Anyone else experience this?

(After the first kernel upgrade the recording freezed and skipped up to 10 seconds, but after driver upgrade it is approx 1 second.)

Another thing,
Sometimes when I am recording and watching the recording (or another recording) the playback freeze or "stutters", pressing rewind or 15sek skipback helps and the playbacks fine again for a while.
It almost seems like there som kind of buffer underrun.

[Erik Slagter]

What box?

[littlesat]

3.1.1. is VU only...

[dAF2000]

Yes, I experience the same problem here, too. It must be kernel related.

[Erik Slagter]

3.1.1. is VU only...

How about ct... Anyway, I don't think it such a bad idea to mention the box what's the question/problem is about...

[Rob van der Does]

3.1.1. is VU only...

How about ct... Anyway, I don't think it such a bad idea to mention the box what's the question/problem is about...

CT/ET is 3.1.0...
Indeed mentioning the box should be mandatory?

[dAF2000]

It's about a VU+duo (see label).
Anyway, the same problem appears on a VU+ultimo too.

[MiLo]

The recording glitches are on the ET too, have to do with the ext4 journaling. There's a German thread about it (that turns into English half way).

The fix is to add the option "nodelalloc" to the mount parameters for the disk. Either using tune2fs or in /etc/fstab.

[Erik Slagter]

So that's why I don't see them (recording on NFS...)

[krister67]

The recording glitches are on the ET too, have to do with the ext4 journaling. There's a German thread about it (that turns into English half way).

The fix is to add the option "nodelalloc" to the mount parameters for the disk. Either using tune2fs or in /etc/fstab.

OK, thanks!
I will try adding "nodelalloc".

BTW.
Do you have an example of a /etc/fstab with that option added?

[krister67]

The recording glitches are on the ET too, have to do with the ext4 journaling. There's a German thread about it (that turns into English half way).

The fix is to add the option "nodelalloc" to the mount parameters for the disk. Either using tune2fs or in /etc/fstab.

OK, thanks!
I will try adding "nodelalloc".

BTW.
Do you have an example of a /etc/fstab with that option added?

Don´t bother, I found the german thread.......

[krister67]

Well, after adding "nodelalloc" to the fstab and remounted the drive the 1sec skipping is gone. (If it´s not because I changed cccam from 2.30 to 2.14 also.)
BUT, the stuttering/stopping during playback still remains....
Is there any other way to fix this?

[krister67]

Well, after adding "nodelalloc" to the fstab and remounted the drive the 1sec skipping is gone. (If it´s not because I changed cccam from 2.30 to 2.14 also.)
BUT, the stuttering/stopping during playback still remains....
Is there any other way to fix this?

Sorry, that should be cccam 2.21 and not 2.14.

[krister67]

Well, after adding "nodelalloc" to the fstab and remounted the drive the 1sec skipping is gone. (If it´s not because I changed cccam from 2.30 to 2.14 also.)
BUT, the stuttering/stopping during playback still remains....
Is there any other way to fix this?

Sorry, that should be cccam 2.21 and not 2.14.

Anyway.... I decided to try change something else so I set the "Recording data sync size"=1 MB (default is OFF) and after that the recordings and playback is flawless.
I have no clue why, maybe it´s just a coincidence.

[Erik Slagter]

I definitely think thay may be a clue. Can you please increase this setting until the problem re-appears? Maybe the (new) default value for the VU+ is not optimal.

Edited by Erik Slagter, 15 February 2012 - 15:38.

[krister67]

I definitely think thay may be a clue. Can you please increase this setting until the problem re-appears? Maybe the (new) default value for the VU+ is not optimal.

The first settting I tried before was to set it to 4 MB, but then if I pressed "pause" for timeshifting nothing happend if I pressed "play", I just got a "invalid"-symbol on the screen.
I will try to increase it to 2 MB and see what happens.

What is the new default setting for VU+?

[Erik Slagter]

I don't know exactly, but there were two options before: sync time and demux buffer size. The latter option has been removed lately and is being calculated automatically, based on fitted RAM size of the box. Both option influence together whether "hicks" appear or not, so if one the demux buffer has changed due to the automatic calculation, the other option, data sync size may need another value to complement. So if you can find out what value works best, that value might be set as default value for your type of box.

[pieterg]

I definitely think thay may be a clue. Can you please increase this setting until the problem re-appears? Maybe the (new) default value for the VU+ is not optimal.

The first settting I tried before was to set it to 4 MB, but then if I pressed "pause" for timeshifting nothing happend if I pressed "play", I just got a "invalid"-symbol on the screen.

That's a different issue, not related

[krister67]

I definitely think thay may be a clue. Can you please increase this setting until the problem re-appears? Maybe the (new) default value for the VU+ is not optimal.

The first settting I tried before was to set it to 4 MB, but then if I pressed "pause" for timeshifting nothing happend if I pressed "play", I just got a "invalid"-symbol on the screen.

That's a different issue, not related

Please explain.

[mire]

I also have some problems in playback, which could be described as glitches. Picture occasionally starts pixelating. Quick +20sec, -20 sec returns it to normal. I believe my disk is in ext3 filesystem, since there is an option to convert it to ext4. I am not sure if I should do that, because I am a complete lamer with linux.

Where are those "recording data sync size" option, and nodelalloc, about which you were talking earlier?