Too many tuners not - enough disk speed?

[autoboy]

This is a question for those with large numbers of tuners. I just recently added a HD Home Run to my server and now have a total of 5 tuners. My system is as follows

Athlon64 3500+
512MB Ram
Windows XP
1 IDE 160GB OS drive 15GB 4K partion and 130GB 64K partition
3 IDE 200GD 64K storage drives no RAID on Via controler on board
2X PVR 150
1 Avermedia HD180 digital TV tuner for OTA
1 HDHR (2 digital tuners) on QAM

The HDHR is on a 100mbit 4 port switch shared with my server. Server network traffic is 35-40% when all tuners are going and I'm watching HD on my client.

I'm having problems with the video skipping when all tuners are recording. This used to be a problem until I stopped having it record on the OS drive. Now that I added another couple tuners it is happening again. Does anyone else have this problem? How can I fix it? Is the OS drive too slow and swapping data all over the place? It seems to happen no matter what drives from the array it is recording to so I figured it was the OS drive swapping all over the place. I added some more RAM (DDR 266 which sucks but works) to get up to 1GB and this did not solve the problem. What else should I try?

[Goodspike]

I started a thread in one of these forums on Sage Service taking up a lot of CPU cycles if running while recording and watching. If you're running service, you could try turning it off while watching and see if your CPU use goes down.

I think I might have determined that part of that problem was related to the use of the free version of Zonealarm. If you're running that you could try turning it off and using Windows Firewall instead.

[autoboy]

I don't use any firewall or virus scanner. CPU usage is low at 15%. It is a dedicated sage server.

[AngelofDeth]

Have you tried moving one of the files that skips directly onto your clients hard drive and see if you see skipping? This would eliminate the network as a culprit. Then it would either be a problem with the client, or the encoded files are actually bad and not a network problem.

[Mark SS]

Open Administrative Tools/Performance and add Logical Disk\Average Disk Read Queue Length and Average Disk Write Queue Length and report back the stats that are logged when problems occur.

[autoboy]

The problem is with the recording. Not the playback. I also switched the HDHR to its own network card on the server so I can get full gigabit speed on my network and git rid of the extra switch. It is still doing the same thing. I also switched the swap space to the extended partition on the main OS drive. It is 64K sectors. Maybe that will help. So far it seems to have worked. I'll check the performance settings next.

[autoboy]

I don't really know what the performace #s mean but moving the swap space seems to have fixed the problem.

[nielm]

for future reference you can also specify a property in Sage.properties for each encoder so they will write in preference to a specific hard drive to help distribute the writes from your HD tuners...

[172pilot]

Originally Posted by autoboy

I don't really know what the performace #s mean but moving the swap space seems to have fixed the problem.

On my system, I've got a similar problem... My "boot' drive is a 250 gig PATA, and my sage drive is a 1TB SATA... Are you saying you put your swap file on a separate partition on your boot drive, and that seemed to help?? I'm getting recordings with all kinds of jitter in them, presumably from overloading my TB drive with multiple HD recordings at once..

Any detail would be appreciated!!

-Steve

[Conejo]

Just rebuilt my SageTV server recently and replaced two PATA 160MB drives with a new SATA II 500GB. Major difference in how my system handles multiple HD recording from the HDHomeRun. Before I had access lights constantly glowing, now I have drive flashes every .8 seconds.

Stealing other people's quotes, I am, because I like to practice my plagiarizing skills:::

Originally Posted by gjvrieze

...from this thread Question about disk i/o impact with multiple tuners

Also, for reference, I have 10 tuners recording to 3 320GB drives in RAID 0 and it barely hits them... 10 streams at 20Mbps is 200Mbps or 25MBps, most modern HDs can run in the 60-150MBps range