Studdering on Vista, why

[carlgar]

I run the SageTVClient on the same computer as the SageTVserver. Today I tried the track down the studdering I have being seeing for the last couple of days. Using the Resource Monitor I see system access to the file at the same time. This access last a couple of minutes and restarts every couple of minutes. Does anyone know what could be going on? Since the system access run at background IO Priority, why should it slow down the normal access? I have attached a screen image of the Resouce Monitor, I am viewing J:\SageTV Videos\NCIS-TrojanHorse-2223010-0.ts. Any suggestions or ideas? The OS is Vista Home Premium.

[flavius]

Does that happen with all files? Only digital recordings?

[davephan]

I noticed that you have only 2 gigs of memory on that Vista computer. I have heard from multiple sources that running 2 gigs memory on Vista gives equivalent performance to running 500 MB memory on Windows XP. Running 500 MB memory on XP results in poor performance, compared to running 1 gig memory on Windows XP. You may need to add memory to bring the Vista computer up to 4 gigs!

Dave

[Trepidati0n]

Originally Posted by davephan

I noticed that you have only 2 gigs of memory on that Vista computer. I have heard from multiple sources that running 2 gigs memory on Vista gives equivalent performance to running 500 MB memory on Windows XP. Running 500 MB memory on XP results in poor performance, compared to running 1 gig memory on Windows XP. You may need to add memory to bring the Vista computer up to 4 gigs!

Dave

That is FUD. Vista gives up memory as needed when other applications are present and require it.

[ToxMox]

Perhaps it is the shadow copy service.

[FidgetyRat]

Comedy Option:

Vista is using 95% of your system's resources just to operate rendering all actual programs useless.


On a serious note, have you checked your drivers / decoders? Does the shuddering also happen with external programs?

[carlgar]

I have only seen the studdering while viewing HDTV and it probably only occurs 1 or 2 times during a 1 hour show. I now usually just pause the show until I see the unknown program go away. The unknown program does do the same thing on all of the recordings both digital and analog. It appears to be reading the file as fast as it can. The background rate seems to slow down the access time, the Read(B/min) count is much higher than the SageTV read rate.

I had seen discussions about the memory, but I do not believe it is an issue. the CPU meter and Multi Meter gadgets both show about 57% memory usage.

I tend to think it is some type of shadow copy or file checking program but I do not understand why it would have to run so often.

I do keep everything as up to date as possible. I have only had the system up for about a week and still getting use to VISTA. I do notice some other delays but I have a good feeling that I know why they occur. I know when I connect to the internet the modem dialing is going to cause a quick studder issue that only last while dialing. A bigger issue is when is when I exit a program it brings the SageTVClient to a halt for a while. I have not timed it but is probably about 30-60 seconds before the SageTVClient resumes play again.

[greggerm]

I demand a lot from my desktop computer, moreso than my Sage server - I run Vista on my "desktop" PC with 2 GB RAM and she works just fine, with no perceived problems.

2 GB is a sweet spot for Vista memory - Vista takes a new attitude towards memory, as it considers unused memory to be wasted memory. Vista will automatically use as much unused memory as it can for caching and other self-important tasks, but the instant the memory is required by a 3rd party application, it will give it up.

Many ill-informed users are seeing high Vista memory usage and immediately thinking the OS is garbage - in fact, it is leveraging your RAM investment far better than previous OS's have.

[carlgar]

The stuttering problem appears to have been caused by the superfetch. I disabled the superfetch when I heard stuttering and I have not seen any more problems since. However, I was on my last HD recorded show for the day, will know more tomorrow. There is a lot discussion in the Microsoft communities about the superfetch slowing down disk access.

[greggerm]

Originally Posted by carlgar

The studdering problem appears to have been caused by the superfetch.

That would make perfect sense - Superfetch trying to cache in something all the while Sage trying to write/read video.

Note to self: if ever installing Sage on Vista, disable Superfetch service!

[mkanet]

I figured this out too! I didnt see this thread until AFTER I did the same thing. I dont know if there's a way to disable it only on the recording logical drive.

[carlgar]

I have also notice studdering while playing a HD show and copying from the same drive to a USB disk. I have not found a work around for this. I either tolerate it or wait until I am viewing a different show.

[mkanet]

There are currently two know issues in Vista for video stuttering/jerky video.

1) Excessive hard disk usage during recordings
Solution: Disable Superfetch Service.


2) Jerky video playing back most 1080i material using Nvidia based hardware acceleration + VMR9 and latest official Nvidia display drivers.
Solution: No good solution yet. You can either buy a new non-Nvidia display adapter or use a non-hardware accelerated mpeg2 video decoder. SageTV engineering is already aware of this problem.