Record 2 shows at 1 time, resource competition?

[steingra]

Just wondering how SageTV+ the underlying hardware in the HTPC can cooperate and record 2 shows at the same time? Wouldnt they be competing for using the same hard drive controller and there have issues with the ability to be writing all this data to the hard drives at the same time, from 2 different PVR Cards? (I have a PVR USB2 and a PVR 150)

[jamjam]

The data transfer rate of the hard disk can easily cope with the requirements to record 2 propgrams at the same time. Not sure what the limit would be but there are people with 3+ TV cards able to record at the same time.

When both cards need to write a packet of data at the same time one would be buffered and written after the first one.

HTH

JJ

[mdmint]

Originally Posted by jamjam

The data transfer rate of the hard disk can easily cope with the requirements to record 2 propgrams at the same time. Not sure what the limit would be but there are people with 3+ TV cards able to record at the same time. JJ

I don't know what the limit is either, would depend on the HD subsystem. There are people with 6 tuners that can record all with simultaneous concurrent playback of previously recorded show no problem, I know for sure (me) and I believe I heard someone is running 8. However, I don't write to a single HD but a RAID5 hardware controlled array striped across 7 disks (plus hotspare 8th drive of array). Whatever your HD configuration make sure your Sage storage partition is formatted 64k clusters else HD will have to seek too often and then can't keep up under heavy loads.

Note: these are SD not HD recordings...

[waynedunham]

Originally Posted by jamjam

The data transfer rate of the hard disk can easily cope with the requirements to record 2 propgrams at the same time. Not sure what the limit would be but there are people with 3+ TV cards able to record at the same time.

When both cards need to write a packet of data at the same time one would be buffered and written after the first one.

I'm running 2 PVR-500's in my Sage Server with Sage and Sage Client running on the box. I've often been recording with all 4 tuners AND viewing a previous recording through Sage Client on my MVP. Like the last poster, these are all SD not HD.

[michelkenny]

I can record 4 SD streams (via 2 PVR-500's) onto the same hard disk (formatted as 64k clusters) and I never have any problems. I can also view a recording while this is hapening too

[steingra]

Originally Posted by mdmint

I don't know what the limit is either, would depend on the HD subsystem. There are people with 6 tuners that can record all with simultaneous concurrent playback of previously recorded show no problem, I know for sure (me) and I believe I heard someone is running 8. However, I don't write to a single HD but a RAID5 hardware controlled array striped across 7 disks (plus hotspare 8th drive of array). Whatever your HD configuration make sure your Sage storage partition is formatted 64k clusters else HD will have to seek too often and then can't keep up under heavy loads.

Note: these are SD not HD recordings...

Yup, I made sure to format the new Raid array using 64k cluster size. I seem to remember setting it in the RAID BIOS settings when I created the array. But I also seem to remember telling windows to use that size when I formatted it

My system seems to be doing nicely at recording 2 shows at same time. CPU usage I think is only like average of 5% when its doing this...? And I havent really watched actual disk activity. I was just curious... its good to know that a similar system is doing 4 streams AND watching one too. Thats nice.