MEngland
03-22-2006, 04:08 PM
Storage Review has the WD 400GB listed on their leaderboard as the best Nearline storage solution:
http://www.storagereview.com/articles/leaderboard.html
If you read through their categories, you will find that Nearline is a pretty good summary of what is needed by TiVo: modest cost, reasonable performance, high reliability. The Caviar Raid Edition (RE2) is rated for 1M hours MTBF and 24/7, 100% duty cycle - Perfect for TiVo.
So here is the question. There is a consumer variant of this drive, the SE. One of the significant difference between RE and SE drives is Time Limited Error Recovery (TLER) on the RE. In simple terms, TLER means that the RE drive will only try for 7 seconds to read or write when it has an error, then it will report the error and move on. An SE drive will keep trying to error-correct, even if it takes more than 8 seconds.
Read more about TLER here: http://www.wdc.com/en/library/sata/2579-001098.pdf
For TiVo use, I would think that errors in reading or writing data data would be seen as nothing more than a slight glitch in the video - no big deal. (Executable code is different, there an error is the difference between the code working or not working. But TiVo spends almost all it's time writing video.)
So, for my thinking, a drive that tries to correct read or write errors for up to 7 seconds and then moves on would be fine for TiVo. What do you think?
http://www.storagereview.com/articles/leaderboard.html
If you read through their categories, you will find that Nearline is a pretty good summary of what is needed by TiVo: modest cost, reasonable performance, high reliability. The Caviar Raid Edition (RE2) is rated for 1M hours MTBF and 24/7, 100% duty cycle - Perfect for TiVo.
So here is the question. There is a consumer variant of this drive, the SE. One of the significant difference between RE and SE drives is Time Limited Error Recovery (TLER) on the RE. In simple terms, TLER means that the RE drive will only try for 7 seconds to read or write when it has an error, then it will report the error and move on. An SE drive will keep trying to error-correct, even if it takes more than 8 seconds.
Read more about TLER here: http://www.wdc.com/en/library/sata/2579-001098.pdf
For TiVo use, I would think that errors in reading or writing data data would be seen as nothing more than a slight glitch in the video - no big deal. (Executable code is different, there an error is the difference between the code working or not working. But TiVo spends almost all it's time writing video.)
So, for my thinking, a drive that tries to correct read or write errors for up to 7 seconds and then moves on would be fine for TiVo. What do you think?