flaws in the scheduling algorithm

[zz5]

This is a bug that's been in Sage since I started using it two years ago. When you have more than one thing scheduled to record at the same or close to the same time, and more than one recording drive, Sage will not always record things where there's room.

For example, I have 4 things set to record. 1 will need 1 gigabyte, 2 will need 2 gigabytes, and 1 will need 4 gigabytes. I have 5 recording drives. The first has 5GB's available, 3 have 2.5GB's, and the other has 1GB. There's plenty of space for all of these recordings, but Sage chooses to record everything but the 1GB recording on the drive with 5GB free.

Is there any way in Studio to set the location and encoder for a recording? I would really like to use my own scheduling algorithm. Even without this bug, it's the only way to make sure that certain things will be recorded if you're going to be gone a few days.

[Opus4]

Originally Posted by zz5

Is there any way in Studio to set the location and encoder for a recording?

No, but if you've got a reproducible problem with the scheduler and/or its recording placement, then I'm sure SageTV would like to hear about it from you.

- Andy

[zz5]

I've sent this bug in a few times in the past. It's happened many times, but I can't really reproduce it, at least without a lot of work. I'm hoping to find some other people who've had this bug. If a recording runs out of space, but you had plenty of space on another drive, that would be this bug. This has happened to me many times. If I catch it fast enough, I can go ahead and delete something so there's enough space.

[stanger89]

Does it throw a conflict, or just reschedule a recording for later?

[Narflex]

Originally Posted by zz5

This is a bug that's been in Sage since I started using it two years ago. When you have more than one thing scheduled to record at the same or close to the same time, and more than one recording drive, Sage will not always record things where there's room.

For example, I have 4 things set to record. 1 will need 1 gigabyte, 2 will need 2 gigabytes, and 1 will need 4 gigabytes. I have 5 recording drives. The first has 5GB's available, 3 have 2.5GB's, and the other has 1GB. There's plenty of space for all of these recordings, but Sage chooses to record everything but the 1GB recording on the drive with 5GB free.

Is there any way in Studio to set the location and encoder for a recording? I would really like to use my own scheduling algorithm. Even without this bug, it's the only way to make sure that certain things will be recorded if you're going to be gone a few days.

I just checked this out and it looks correct in SageTV so it should be doing what you're asking it to do. If you can reproduce the problem and send us the detailed information we'll gladly look into it. http://sagetv.com/bugs.html

[zz5]

Thanks for the responses, everyone.

Let me give some more information about the situation that produced the bug above. I only use manual recordings. I don't use any favorites. So the question stanger89 is asking wouldn't apply. I know that most people do most of their recording with favorites, so most people wouldn't really notice this problem. I have seen a few people post about running out space and wondering why Sage scheduled a recording on a certain drive. I've sent in support requests in the past but so far they haven't been able to figure out the problem. It's just something I know can happen from time to time so I try to watch out for it, which is how I caught it this time.

Since this has happened many times in the past, I've taken notes on it to see if I could figure out what is happening. The thing that makes the problem difficult is that it doesn't happen every time. 3 out of 4 times it will work right. It's a pain to set up a test because you have to fill the drives up.

I have a few ideas about things to check:

The 4GB recording last night was a one hour show padded at the end by one hour. I pad all the shows by 2 minutes at the end and beginning. Is it possible Sage doesn't take into account padding when estimating recording space needed? The shows would have fit witout that extra 2GB worth of padding on that one show.

Is it possible there is some latency somewhere? Maybe Sage schedules ahead of time. Maybe when Sage queues resources, either because of Java or Windows there's some latency in reporting how much space is left.

Another idea is that maybe it's just something specific with my setup. Even though I've used Sage with three different motherboard chipsets and have always had this problem, I've almost always had a 350 mixed with 250's. This mix has caused problems and still has a few problems I have to work around. I have no specific reason to think so, but maybe the 350 is preventing proper resource queuing.

Another idea is that maybe Sage is just overestimating the space needed by a lot. If this is what it is, then it's not really a problem because I would just make sure I had more space.

Anyway, I'm just throwing out some ideas. Thanks for testing this out, Narflex.

[Narflex]

SageTV does take padding into account when estimating the space needed: CHECK

Latency; SageTV does keep a little buffer of disk space, probably around 500MB per drive (depends upon a few things).

It may be overestimating the space...are you using VBR or CBR qualities to record? CBR is very accurate with estimation but VBR is usually off somewhat.

[zz5]

Thanks Narflex.

The recordings in my example above were all in Great mode so that would be CBR.

I took a look at the notes I made when trying to figure out this problem in the past. I will have to do some more testing to see if the problem is just needing to have a little more free space per drive.

[jominor]

Originally Posted by Narflex

SageTV does take padding into account when estimating the space needed: CHECK

Latency; SageTV does keep a little buffer of disk space, probably around 500MB per drive (depends upon a few things).

It may be overestimating the space...are you using VBR or CBR qualities to record? CBR is very accurate with estimation but VBR is usually off somewhat.

Does the setting that tells Sage to keep X amount of space free influence that buffer? I have all my drives set to keep 5gig free(for things defragging).