Separate names with a comma.
Discussion in 'TiVo Series3 HDTV DVRs' started by opus472, Apr 20, 2008.
Any idea why a reboot takes so long on these boxes? Way longer than even Windows Vista...
I would say it has to do with the processor, but I could be wrong.
What is Tivos processor equivelant to? A Pentium I ?
TiVo runs their own software on top of Linux.
The high-definition TiVos use a MIPS 300MHz processor comparable in performance to an Intel Celeron 300, but with built-in MPEG decoding with dedicated hardware acceleration for DVR functions.
A number of other consumer electronics devices are also based on Linux and boot much faster because they load an image from flash memory (similar to suspend/resume on a PC). TiVo could do something like that with a future model.
To the above, I would add that TiVo would be wise to consider a move to a flash-based design for its system software. In the past, one had to trade off capacity (and thus software upgrade potential) with flash, but that is no longer the case.
Currently, TiVos start to crash / reboot when a problem develops with the software. A flash-based design would ensure that the software remains stable when the hard disk starts to develop problems.
I agree with everything you say excpet that you get 2 out of 3 of large, cheap, reliable.
Can TiVo truly get a large enough flash memory hardware that it can rely on while not jacking the price up too much?
The series 4 is at least a year off. maybe by then?
If they can give away thumb drives, yes.
If it were me, I'd run a boot OS and have the loopsets and root database on the Flash drive.
Really though, it isn't the drive interface slowing things down, it is a whole bunch of little procedures and modules it is loading taking time, as well as the kernel security check. I noticed when I hacked my 240, that it booted that much faster when I disabled the kernel security check.
I'd say the slow boot time is because it's Linux on a low powered processor. If a system is architected properly, it should use almost all of it's bandwidth during normal operation with little to spare. The Tivos are not like PCs where PC makers don't know what applications will be run and the user directly sees performance increases for higher powered CPUs, more memory, etc (i.e. more hardware costs). CE makers have a compelling need to "right size" hardware to their application. Boot time is a busy time for any OS, so it's slow.
Flash would be installed on the mainboard and flash does fail. Yep, you could use removable flash but that's a compatibility headache for Tivo and how would you reload it, your hard disk?
Tivo partitioned it right. All of the higher reliability parts on the mainboard, hard drive and power supply external.
Why should it be fast?
In an ideal world, the TiVo never reboots. In the real world (if it's on a UPS), it reboots maybe twice a year. To refer to the OPs comparison, many folk have Windows up and down more than once a day -- no wonder MSFT is interested in a fast boot -- it's a big part of the Windows experience.
True, but it still shouldn't take 5 minutes to reset - especially on a Linux based OS. I have an old desktop with 512Mb running Ubuntu that does better!
Anyway, the fact that TiVo uses Linux does mean that it should stay running longer... much longer than any Windows machine, and without the weekly patches / forced reboot cycles!!
So does your desktop get two tuners set to recieve input - possibly having to decrypt it or decode/encode to mpeg2 and then write both of those streams to the same hard drive it is booting from along with adding in encryption of those writes to the drive?
Oh and also look for scheduled events (recording) that should be happening and perform those if needed.
This is all in addition to the mormal startup items.
I think if so then the desktop just might boot a little slower
Spoken by a person who doesn't understand flash-based storage.
There are many different types of flash and believe it or not, some are actually *slower* than a decent hard drive for some types of operations (writes in particular).
On a gigabyte basis, hard drives are considerably cheaper than decent flash drives - yes, you *DO* trade off capacity when going from hard disk to flash. On a IOPS basis, it can go either way depending on the operations you're doing.
Those little thumb drives they give away at conferences aren't all that great and definitely not something I'd want to see in my TiVo.
None of that is happening during the boot process. But thanks for the misguided attempt at sarcasm.
Windows Vista boots up very fast for me on my 3 Vista machines. Faster than my Xp machines.
I think you are a bit confused. Nowhere did I suggest that TiVo completely replace the hard drive with flash memory.
I suggested that TiVo follow the same model used in other modern CE devices -- such as cell phones and upcoming Blu-ray players. This puts the OS software on non-volatile flash as a pre-booted Linux image. This is much faster, because you are loading a 'pre-booted' image into memory rather than booting the OS. Recordings would still be stored on the hard drive.
The Linux OS and TiVo software total less than 400Mb. Total boot time with this implementation should be around 30 seconds.
Nor did I suggest that. I'm talking about non-volatile flash memory devices of appropriate size (i.e. 512MB-1GB) specifically designed for this purpose. A number of manufacturers produce these flash devices for cell phones, music players, and other consumer electronics devices. With the aquisition of M-Systems, Sandisk is perhaps the best known manufacturer of these disk-on-a-chip devices. Here is their marketing video on YouTube.
These products have been around for awhile, but only in the past year or so did they become available in volume at capacities greater than 256Mb. Sandisk's product is now available in volume at 512MB, 768MB, 1GB, and 2GB sizes.
Well, the boot process does indeed take a while, but there's a lot going on there. Your comparison to Vista is apples and oranges. Fudging just a bit, when Vista is done booting, your PC is only more or less at the point where the "Just a few more minutes" screen pops up. A better comparison would be to set your Windows Startup to automatically run MS Access and load a 500M database file, run a web server, and start playing two HD videos. Start your stopwatch when the power is turned on and stop it when all the applications are fully up and running.
Of course, no matter what, the comparison isn't going to be perfectly one for one, and it's quite possible your PC might still beat the TiVo, but as others have pointed out, fast booting is just not a high priority in a DVR.
This is just my opion as an answer to your question
When I had a DVR cable box it would boot in less than 30 seconds except there would be no guide date in the box, it would take an hour before you would have a days worth of guide data and a day or so before you would have all the two weeks of guid data. I think when TiVo re-boots it has to re index all the guide date because it make no assumptions as to how long the TiVo has been off. This takes time but in about 4 minutes you have your TiVo back with ALL the guide data out about two weeks (unless the TiVo was off for more than a day )
There's probably also some disk-checkng (fsck) time thrown in.
it runs e2fsck on the /var partition on each boot. if /var gets rebuilt, it only takes about 30 additional seconds.
BTW, my S1s are WAY WAY WAY WAY faster in booting than my S3 or TivoHD.
Also, the S3 & TivoHD do some kind of channel scan upon reboot too, which takes a while.
My S1 with 700gb and a 512mb cachecard is also faster than my THD.