interruptions while playing songs

[catawompus]

I have an H340 with the latest current build installed. Sometimes, when I start playing a new album (and only then, never in the middle of an album) there's a short interruption, sometimes two, at the beginning of the first song. It doesn't happen with all albums and it doesn't always happen with the same album. Any ideas what could cause this? Thanks in advance!

[bassistguy]

I had the same problem with my Gigabeat F60, and my "fix" was enabling Directory Cache, that way it doesn't have to load song data in to memory at the beginning of each song (I'm assuming that's what was causing the pauses).

[Llorean]

Please research what features do *before* trying to explain them to others.

Directory cache caches filenames and paths to files. It makes browsing files easer, and because it maintains a list of all the files in your player, can make certain operations a bit faster. One thing it won't do, though, is affect buffering in any significant manner. When you start buffering, it loads several songs (approximately 29MB) into memory. This means that only every few songs does it need to rebuffer (and thus re-access the disk). Meanwhile, while it's buffering, the load should be pretty constant whether dircache is on or off.

If enabling dircache fixed it, it's not because "it doesn't have to load song data into memory", as it'd be impossible to play songs without loading them first.

[catawompus]

Llorean, do you have an explanation for my problem?

[Llorean]

No. If I'd had an answer, I would've said it.

[catawompus]

Is it possible that a certain theme has got something to do with my problem? When I was using Cabbie default it would occur on and off, now that I use Ultima it seems to be gone as far as I can tell...

[flinchbot]

I have this often when first turning mine on. It does what appear to be commits to the database and the player can't keep up for the first 5-10 seconds. After that, flawless playback.

[erik7]

My first post on this forum, because since a long time I have problems with Rockbox.

I have the interruptions too and it seems like it happens when you have lots of songs in the directory you are playing music from.
First I had 2000 songs in one directory, then 500 and at last 250. When playing a songs from one of the 'big' directories I get the interruptions.
'Smaller' directories (20-25 songs) don't have it.

Hope it make sence and somebody can do something with it.
I'm having a iRiver H320, latest Rockbox build.

[NicolasP]

This issue seems to be the same one as described in FS#8260. It seems to have been introduced by r15444 (confirmation welcome). Increasing the default chunksize has helped in some cases, but not solved the problem. It is belied that the issue is in the thread scheduling and priority, but by attempts to fix it have been unsuccessful so far.

[Sherv]

My first post on this forum, because since a long time I have problems with Rockbox.

I have the interruptions too and it seems like it happens when you have lots of songs in the directory you are playing music from.
First I had 2000 songs in one directory, then 500 and at last 250. When playing a songs from one of the 'big' directories I get the interruptions.
'Smaller' directories (20-25 songs) don't have it.

Hope it make sence and somebody can do something with it.
I'm having a iRiver H320, latest Rockbox build.

Interesting, I have this issue on my 80 gig iPod vid no matter how many songs are in the directory. Having directory cache ON has reliably resulted in stuttering and interruptions far more frequently than when I have it off, but even with it off there are stutters. As mentioned by flinchbot, this occurs most heavily when the player is first turned on (from what little I can tell, it appears directly related to the buffers are being filled) but unlike flinchbot I experience this randomly as I listen to music (I originally thought it was high-bitrate related but that doesn't seem to be the case).



Thanks for checking into this

[GodEater]

The testing that I've done into this issue seems to suggest that the level of stuttering increases with the depth of the directory tree that the music files are buried in.

I made a test directory off the root of the player with around 70 files in, and couldn't get any stuttering at all when playing back the files in it.

When I moved the entire directory to about four folders deep into my music hierarchy though - the stuttering was apparent straight away.

[erik7]

I'm glad this subject gets full attention.
The files on my player are 2 directories deep.

Root -
          Top 2000 -
                           0001-0250
                           0251-0500
                           etc

Hope this issue will get some piority.

[Lear]

This issue seems to be the same one as described in FS#8260. It seems to have been introduced by r15444 (confirmation welcome).

Hm, r15444 mainly affected ipods (and the h10), so we might have different causes here...

Increasing the anti-skip buffer ought to help re-buffering issues (if so, increasing it to 15 or 30 seconds should be enough). For ipods, it could hide the probably slower disk spin-ups from r15444.

Otherwise, one reason could be that file open isn't very fast. This would match the behavior of big or "deep" directories causing problems (either makes locating the file file on disk slower), while enabling the dircache can reduce or eliminate the problems. Using album art could make things worse (at least without dircache). Making sure the CPU is boosted before opening files in playback.c (including for album art and metadata) might help.

For the initial buffering, maybe it just more data needs to be buffered before actual playback is started (so that slow open calls doesn't cause the filebuf to go empty). I couldn't figure out what triggers pcm playback to start though...

[catawompus]

All I can say that in my case the depth of the directory tree has probably got nothing to do with the skips. I have a folder "music" in the root of the player. What's in there is all subfolders of single albums with an average of probably 12 tracks  and some bigger ones in case of a double album. There are no further subfolders.
The skipping disappeared when I changed themes from Cabbie default to Ultima.
Thanks for looking into this issue.

[Lear]

I have a folder "music" in the root of the player. What's in there is all subfolders of single albums with an average of probably 12 tracks  and some bigger ones in case of a double album. There are no further subfolders.

But how many album folders? Sounds like it could be quite a few. That could make sense, as for some albums the file open "search" would take longer.

The skipping disappeared when I changed themes from Cabbie default to Ultima.

Thus no album art, which would reduce the slow file open problem noticeably.

I wonder if adding a yield() call towards the end of search_albumart_files() could help...