Controller Performance Problem

[EliteAV]

Apologies if this has already been discussed before.

I received my Duet today and have set the controller up to control an existing SB3. The SB3 has a wireless connection to a Vista PC running SC 7.0.1 with a wired connection to a NAS where the media files are stored. I am very happy with the controller and all aspects of performance - with one exception, are very good.

When I select an album from New Music that I havent previously selected, it can typically take 10 seconds from selecting the album (i.e. clicking the centre select button with the album thumbnail selected) to seeing the track listing. With albums that have a larger number of tracks i.e classical, the track listing is never actually displayed (am guessing some sort of timeout is occuring after 1-2 mins). From an unscientific check, it seems to take about 1 second per track before the track listing is displayed. From this, I am guessing this is due to the controller generating/fetching a thumbnail for each track.

Once an album has previously been viewed using the controller, the track listing will display in 1-2 seconds. When using the SC browser interface, this is how long it takes to view the tracks for any album - whether previously accessed from music library or not.

I had previously noticed a similar issue with the SC7 interface if artwork is enabled for track listings (i.e. in the now playing/playlist pane); displaying the album thumbnail for every track results in the SC7 UI being unresponsive and causes the music playback (on the SB3) to stutter, if for example you choose to play all tracks from an album. I have therefore disabled artwork for each track, however, I am guessing that this setting isnt picked up the controller?

[EliteAV]

Ben

As per the following link:

http://forums.slimdevices.com/showth...hlight=artwork

Can you confirm whether the Controller always generates thumbnails for each album track even when this has been disabled as an SC preference (hide artwork)?

Thanks

[EliteAV]

It looks like another user - BillS has experienced very similar behaviour to the issue I have noticed:

....Usability: I’ve found the controller to be responsive, though there are periods of delay, even with a good wireless signal (note my 4K+ albums). Periodically, selecting "Artists" or "Albums" to search or browse, results in a 10-15 second pause before presenting the list. For browsing, once the list is loaded, the remote is very responsive. Bill

This is taken from thread: http://forums.slimdevices.com/showthread.php?t=44425

I see the problem regularly when I select an album on the controller that I havent viewed before and yesterday when I selected New Music (which should return approx 20 albums), the controller appeared to lock up and didnt return any albums for several minutes (SC7 returned the same list via IE in a few seconds).

Has anyone else (who uses their receiver or SB3 wirelessly with SC7) noticed the same issue?

[radish]

I haven't noticed the issue you are seeing. I would point a couple of things out though based on what you've said so far.

1) It's my understanding that the thumbnails needed for SBC display are generated on the server during the artwork scan, not on demand. This is done specifically to avoid issues like this which can spoil the "experience". You can check the status page to make sure the artwork portion of the scan is running and is taking a reasonable amount of time.

2) From what I can tell the artwork grabs are async with the track listing grabs. In other words, if for some reason it is slow to get artwork (and I've seen that at various points in the beta process) the track listing still comes up quickly, but the art thumbnails are loaded afterwards. If you're seeing the listing itself not coming up quickly I'd suspect a different (though possibly related) issue.

You said the music is on a NAS but the server is on a PC, what is the connection between the two? Is the server's DB and cache on the PC or the NAS?

[EliteAV]

I haven't noticed the issue you are seeing. I would point a couple of things out though based on what you've said so far.

1) It's my understanding that the thumbnails needed for SBC display are generated on the server during the artwork scan, not on demand. This is done specifically to avoid issues like this which can spoil the "experience". You can check the status page to make sure the artwork portion of the scan is running and is taking a reasonable amount of time.

2) From what I can tell the artwork grabs are async with the track listing grabs. In other words, if for some reason it is slow to get artwork (and I've seen that at various points in the beta process) the track listing still comes up quickly, but the art thumbnails are loaded afterwards. If you're seeing the listing itself not coming up quickly I'd suspect a different (though possibly related) issue.

You said the music is on a NAS but the server is on a PC, what is the connection between the two? Is the server's DB and cache on the PC or the NAS?

Radish, thanks for your thoughts on this (I thought for a while this thread was going to be a bit of a one sided conversation;-)

The artwork scan on SC7 has been completing successfully (I am not at home at the moment so cant check the run time) as I can see the artwork in various sizes via the SC7 interface.

What I have noticed though is that if I have Show Artwork enabled on SC (i.e. in the playlist pane), it definitely takes longer to populate than just showing text descriptions for each track. As previously noted, this was affecting the playback of the first few seconds of a track i.e. the SB3 or receiver would "stutter" until the playlist (in SC) had been fully populated with thumnails for all tracks in the playlist. This suggested to me that on SC at least, the display of thumbnails for tracks & subsequent playback was a synchronous process. Disabling artwork (in the playlist) fixed the lag/stutter problem.

What I am seeing on the controller mirrors the above problem on SC. However, whereas disabling artwork fixed the lag issue on SC, it didnt on the controller. When scrolling through a list of albums on the controller, the thumbnails are being generated asynchronously as the artwork fills in as you scroll which is a nice way of doing it. However, selecting an album or New Music is when I see the lag.

This was the reason why I surmised that if you click on an album with say 12 tracks, the controller was making 12 requests to SC to fetch a thumbnail from it's cache for each track (& for albums, I would expect every track to just use the same album artwork anyway unless a different image had been embedded in the file).

Perhaps the artwork is a red herring, or perhaps it only manifests itselfs with wireless networks (where there is a bit more latency). I am sure that one of the developers could answer this fairly quickly, but am not sure how to raise this with them, short of waiting for them to stop by the forum. I think the controller is a brilliant product (& I realise that it will get better with each firmware release), but at the moment, these lags do spoil the usability somewhat. I have a strong wireless signal and in all other respects, the controller navigation performance is very good.

Just as an FYI, I have SC7.0.1 running on a dedicated Vista PC dual core/2GB RAM) with a wired connection to my (Infrant) NAS. SC's cache & db is on the PC in the default location. I have a wireless connection from my SB3 and receiver to the PC server.

[radish]

What I have noticed though is that if I have Show Artwork enabled on SC (i.e. in the playlist pane), it definitely takes longer to populate than just showing text descriptions for each track.

That doesn't surprise me, this is a web page after all so each element is a seperate request and assuming your browser is following the normal rules it will only make a couple of requests in parallel at a time.

As previously noted, this was affecting the playback of the first few seconds of a track i.e. the SB3 or receiver would "stutter" until the playlist (in SC) had been fully populated with thumnails for all tracks in the playlist. This suggested to me that on SC at least, the display of thumbnails for tracks & subsequent playback was a synchronous process. Disabling artwork (in the playlist) fixed the lag/stutter problem.

It's not synchronous, but it does sound as if one is stepping all over the other. For whatever reason, the server can't get audio data to the player and get images to the browser at the same time. Normally I'd say there was an issue with disk I/O, CPU or network bandwidth but from your descriptions those shouldn't be an issue. Have you tried the server performance tests under Help?

What I am seeing on the controller mirrors the above problem on SC. However, whereas disabling artwork fixed the lag issue on SC, it didnt on the controller.

Well, you can't disable artwork on the controller

When scrolling through a list of albums on the controller, the thumbnails are being generated asynchronously as the artwork fills in as you scroll which is a nice way of doing it. However, selecting an album or New Music is when I see the lag.

They shouldn't be being _generated_ but rather transmitted, they should all be in the server's cache. Regardless, my guess here is that the call to get track album art is sync as it was assumed the list would be much shorter. But that's only a guess.

This was the reason why I surmised that if you click on an album with say 12 tracks, the controller was making 12 requests to SC to fetch a thumbnail from it's cache for each track (& for albums, I would expect every track to just use the album artwork anyway unless a different image had been embedded in the file).

Yup, I would think that's what's happening. You can't make assumptions about the image being the same though, as albums and playlists aren't treated differently. I would think the initial request for track data includes the filename/URI of the image - the controller caches some itself so I assume it's smart enough to only request a given image once.

I am sure that one of the developers could answer this fairly quickly, but am not sure how to raise this with them, short of waiting for them to stop by the forum.

They're around plenty In your case where there isn't a clear bug I wouldn't suggest a ticket right away, but you might want to give the helpdesk a call if you continue to have problems, they're pretty good at this stuff.

[EliteAV]

Well, you can't disable artwork on the controller

Sorry, what I meant was that I believe that the controller shares some of the user settings with SC7, so if you choose to hide artwork for *track* listings on SC7, you dont see thumbnails for *track* listings on the controller.

They shouldn't be being _generated_ but rather transmitted, they should all be in the server's cache. Regardless, my guess here is that the call to get track album art is sync as it was assumed the list would be much shorter. But that's only a guess.

Again, wrong choice of word on my part:-), by _generated_, I meant displayed by reading from the server's cache as you have stated.

They're around plenty In your case where there isn't a clear bug I wouldn't suggest a ticket right away, but you might want to give the helpdesk a call if you continue to have problems, they're pretty good at this stuff.

I will do some more testing to see if I can see a pattern (once I have viewed all tracks for an album, I dont see the lag again for that album which does point to the controller cache being involved somewhere). Failing this I will log a call with support.

[Rar]

I experience a similar problem. Sometimes it just takes ages for the controller to load "Artists". Very annoying, when trying to skip to something different. Can't seem to find a pattern. The connection is very good.

And a sidenote: It's not logical that in order to start in the middle of an album, you need to select the entire album and then skip to the track you wan't to hear. If you select a track it should just continue with the next song on the album.

[EliteAV]

Reassuring to know that this is a known issue:

On the delay when hitting search Artists/Albums (you didn't mention Tracks, which will be MUCH worse): I fixed that on our development tree and you'll see that delay disappear entirely when 7.0.1 is released.

From post: http://forums.slimdevices.com/showthread.php?t=44425

I have been using the beta build of SC 7.0.1 from a couple of weeks ago & still see the problem, but perhaps this is fixed in a later revision.

However, as some of you may have noticed from my posts in another thread, I am currently waging a seemingly hopeless battle trying to get my receiver to maintain a network connection for more than a day, so controller performance is no longer a top priority for me at the moment.

[radish]

And a sidenote: It's not logical that in order to start in the middle of an album, you need to select the entire album and then skip to the track you wan't to hear. If you select a track it should just continue with the next song on the album.

http://bugs.slimdevices.com/show_bug.cgi?id=5981