Slow EHD transfer

[Tugboat]

I have a 250G WD in a USB 2.0 enclosure that nets roughly 36MB/s transfer as tested by HD Tach on my PC. However, when it is connected to my 722, it has a transfer speed of roughly 3.6MB/s sending to the receiver and about twice that trasfering from the receiver to the EHD. It takes about 30 minutes to transfer a 6550MB recording from the EHD to the receiver.

Is the 722 picky about the USB enclosure used? I've tested this unit on several desktops and laptops and the speed is always over 30MB/s.

Thanks

 

[RickDee]

That's about the transfer rate as on my 622.

 

[Tugboat]

At the rate of 3.6MB/s it would take 20 hours to transfer a full drive.

The transfer rate is so slow that I can't watch HD shows from the drive without pauses, etc. I have to transfer it back to the receiver to view them. The worst ones are OTA HD recordings. Their bit rate is much higher and are impossible to view off the drive.

 

[Dah-Henny]

When I first transferred my movies over to the WD My Book Essentials, it took a long time, about 15 minutes average per HD movie.

 

[Tugboat]

Maybe it has something to do with conserving bandwidth. I wonder what the internal drives MB/s rating is. Maybe they factor in what would be needed to record two events and playback a third and what's left over is what the EHD transfer rate is set around. I'm sure most would rather have a slow EHD transfer than dropouts in their recordings or playback because the internal drive is maxed out for transfer rate. Hmmm....

 

[navychop]

Are you using the same cable when testing on the PC and for the ViP?

 

[David_Levin]

Yes, the transfer rate is slow, but you should be able to watch directly off the drive. You gave an example of 30 min for 6550 MB. is that a 2 hour movie? Since the transfer is faster then the runtime you should be able to watch it. If it's studdering perhaps the usb interface is not stable. You could try a different cable.

And yes, I believe the usb interface is picky. I also think the 622 is more picky then the 722. I have a drive that works fine the 722, but is unreliable on the 622 (the drive corrupts and I have to use linux to correct).

 

[Tugboat]

Yep, it's the same cable used for both PC and STB testing. I've tried two different 2.0 certified cables.

The 6550 is a 1 hr show off a local HD station (CBS). Each time I watched it, it would play for about 30 seconds, pause for a second or two and start again. If it were a file played on a PC, it would probably be showing dropped frames, but I don't think the STB does the same (it seems to pause to get caught up).

I have noticed something else. I selected two HD movies that I wanted transferred to the drive. When the transfer started I went back to viewing live TV. About an hour later I looked and only one had transferred. I selected the movie again and started the transfer. I checked back about 20 minutes later and it was still transferring. I left it on the status screen and when it reached around 5 minutes remaining, the status went away and back to live TV. When I checked, the movie was not transferred. A third attempt was successful. The same also happened with a couple of HD recordings I tried to restore. It took 2 attempts to get them back. No error messages, nothing.

I don't think it's the drive as I've been able to "stress" test it and it hasn't overheated or generated any errors.

Hmm.... I'm not confident in the abilities of this drive or STB. Don't really want to lose any recordings. Might try a different drive (WD sent me a few deals I might take them up on).

 

[David_Levin]

Is this the first time you're tried this drive on the 722 ?
Is the drive a 3.5 or 2.5" ?
What's the drive speed (RPM) ?

 

[Tugboat]

Is this the first time you're tried this drive on the 722 ?
Is the drive a 3.5 or 2.5" ?
What's the drive speed (RPM) ?

I first used it on a 622 and transferred all the programming to the 722. It didn't have an issue back then and I didn't stick around to see how fast/slow the transfer rate was, so it might have been slow back then as well. That was about 18 months ago.

It's a 3.5" WD2500JB 250G w/8MB buffer and 7200 RPM (I believe it's the same drive as used in the 622).

 

[David_Levin]

That sounds like it should work. I just wanted to make sure you're not trying to use a laptop drive.

All I can say is that I've never used a drive that didn't allow playback directly from the external.

 

[Tugboat]

I found I can play directly from the drive if it's an MPEG4 recording (I'm assuming it is as the size is over 1/2 less than OTA recordings). It's the larger MPEG2 recordings that pause.

Oh well. I wanted a new/larger external drive anyway. Gonna take WD up on one of their specials they keep sending me. The prices are in line with discount on-line stores and no tax or shipping.

It's really too bad they don't include a firewire port. The coding of firewire makes it better at drive transfers. On all the PCs I've tested, a firewire drive does better than a USB 2.0.

 

[harshness]

Chances that any data bus technology will improve the transfer rate is probably next to nonexistent. You're more likely to derive benefit from going to single mode or turning off the DVR.

The question I have: Why would anyone transfer a program back to the DVR?

 

[MikeD-C05]

Chances that any data bus technology will improve the transfer rate is probably next to nonexistent. You're more likely to derive benefit from going to single mode or turning off the DVR.

The question I have: Why would anyone transfer a program back to the DVR?

Presently in the 922 case , to be able to actually watch the recorded shows you have archived.

 

[Tugboat]

Chances that any data bus technology will improve the transfer rate is probably next to nonexistent. You're more likely to derive benefit from going to single mode or turning off the DVR.

The question I have: Why would anyone transfer a program back to the DVR?

Well when one can't watch a program stored on the EHD, one would want to transfer it back to the DVR so it can be watched.

 

[KKlare]

The 8MB buffer should be adequate but most large drives come with 16 or 32MB buffers. I would avoid buying even a small drive like a 250 or 320GB with only an 8MB one. Yes, the OTA HD takes 4500 to 7000MB/hr to record and thus close to the available bandwidth. If in doubt, as someone suggested set the two tuners to an SD channels, which run less than 900MB/hr and both to satellite. The MPEG-4 signals run 1700 to 2200 MB/hr. I've never seen a bottleneck on my 722s with any of the 5 brands of 9 drives but the lowest is a 750GB WD.
The internal-external transfer is given the lowest priority and thus runs slowest, even lower than when used for playback, since there is no latency problem and they don't want one for the input paths even if OTA is selected.
-Ken

 

[harshness]

Presently in the 922 case , to be able to actually watch the recorded shows you have archived.

The OP mentions a ViP722.

 

[harshness]

Well when one can't watch a program stored on the EHD, one would want to transfer it back to the DVR so it can be watched.

It sounds like you need to return the relatively small archive drive to computer use and get yourself a drive that works. I'd recommend something in the 750GB to 1TB range.

Fighting with it is only making you miserable and no amount of collecting statistics and insight is going to fix it.

 

[MikeD-C05]

The OP mentions a ViP722.

Sorry didn't see the 722 reference ,but he was asking why anyone would transfer a show back from the external hard drive to the receiver. In the 922 case that is the only way it works , for now.

 

[Tugboat]

Well I'm going to get a lager external next week. I hope it solves the issue. I'm looking into a 1TB from WD.

If the problem doesn't go away with a new drive, it has to be the receiver's USB or a bug in the OS. Wish me luck.