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View Full Version : TIVO stutters.


martin18152
02-04-2003, 02:13 PM
I know this subject has been beat to death, but let me beat on it a little longer. I have two TIVOS, the oldest types; one has two drives 66 hours, the other one large 80 gig, something like 88 hours. The large drive was installed about 6 months ago. The large drive started to stubble, or stutter. During the stuttering or stubble, pause time would build up. IF you let go, it would max out at 30 min. It got progressively worse over time. All drives in both tivo are Maxtor, except the dual drive, the "a" drive is an original quantum, and the "B" is a Maxtor. All drives are 5400 rmp. The dual drive unit has been going strong for aver a year now. I pulled the supposed bad 80 gig Maxtor, and did the entire test, errors were found, and fixed. I did a low level format, it took 6 hours. The drive passes all certification tests. Loaded the back up from 6 months ago, I think it was the same software load 3.01 or something like that. Put the drive back in the TIVO, no stuttering for about 10 min. Looked good, so lets make the phone call, as soon as data loaded, massive stuttering occurred during indexing, let it continue to index to completion, massive stuttering still going on. Pulled the drive, replaced it with a new drive, 7200 rpm, all has been fine for weeks, not even one stutter, at least while I have been watching.

I have been reading that TIVO uses sequential read and writes, this makes sense for video processing; however, it not very efficient use of disk space. I would think they would use some combination of both sequential and random, in order to maximize space, and read speed. I also read that this problem started around thanks giving for a lot of people, may or may not be significant, depending on the number of users. I know all the guidance tells you to use the 5400 drive, and that the 7200 is unnecessary; however, is it possible TIVO has decided to store data in areas that push the 5400 rpm to the limit, and that any slight slowing of the drive over time would cause a data lag in the buffers. What causes the TIVO to automatically pause? Do the factory tests check seek time, and is the test “pass” adequate for TIVO? What is the minimum seek time required for TIVO to Play, record, and access dynamic data stored on the drive/drives. If I have a dual drive system, and I have a suspected problem drive, can you pick the “a” or “b” to possibly make it work?

I’m in the process of finding a lot of information to answer some of the above question; however and help of direction would be appreciated. I am about to try a few things with the bad 80 gig, like installing it as a second. I will keep anyone interested informed.

FreydNot
02-05-2003, 02:00 AM
Maybe the drive is fixing bad sectors by maping in reserved good sectors. If thats the case, it can make what should be a series of sequential reads jump all over the place without warning.

just my $0.02

martin18152
02-05-2003, 08:40 AM
Thats a thought, dammaged sectors would have to be relocated, but I don't think repaired sectors link anyware. If you do a survey of the drive, dammaged sectors show up as not usable. The dirve shows no dammaged sectors, all are usable. I think that even if you had a dammaged sector the sequential write would just go to the next, and 9 ms seek is and average for random seek, the seek time around a damaged sector would be considerably faster, it shouldn't have a big affect on the buffer. I don't really know a lot about HDs, most of the stuff I do know dates back a few years, when I use to write a little code for floopy and tape drive systems.

I am going to read up a little on modern HDs, might get a revalation, lol.

Thanks for the Input