guru wrote:As for Seagate RAW Error Rate, something for you to chew on.
Seagate SMART Raw Error Rate = 10 * log10(NumberOfSectorsTransferredToOrFromHost * 512 * 8 / (Number of sectors requiring retries)) Where the factor of 512*8 is used to convert from sectors to bits. The attribute value is only computed when the number of bits in the "transferred bits" count is in the range 1010 to 1012
This may not be true for the latest platform...... And I suggest IMHO ;o) that you start another thread for this subject
Once again, thank you for the enlightening information.
Having said that, I'm not surprised at the logarithmic relationship. I had already arrived at a logarithmic relationship for the Seek Error Rate attribute, but I confess that I would never have deciphered the RER.
http://groups.google.com/group/microsof ... 48939aab6ahttp://groups.google.com/group/microsof ... cc5ff526d9 (erratum)
To test the RER formula, I input the threshold values for several of my Seagate drives.
http://www.users.on.net/~fzabkar/SmartUDM/http://www.users.on.net/~fzabkar/Smartctl/ST313021A (13GB, U8) - 0
ST340016A (40GB, Barracuda ATA lV) - 34
ST3120026A (120GB, 7200.7) - 6
ST3320620A (320GB, 7200.10) - 6
I took the liberty of rewriting the formula as follows:
(# of sectors requiring retries) / (NumberOfBitsTransferredToOrFromHost) = 1 / 10 ^ (RER / 10)
AISI, a threshold of 0 gives an implausible result of 1 errored sector per bit transferred, and a threshold of 6 suggests 1 errored sector for every 4 bits.
The threshold of 34 equates to 1 errored sector in every 2511 bits. Even that seems unreasonable to me ???
Further on the subject of read errors, here is a thread which shows some curious results for a vertically mounted drive:
http://forums.seagate.com/t5/Internal-A ... /m-p/42506Do you know of any reason why a drive should behave so poorly in a vertical orientation as opposed to horizontal? And it's not just the one drive, but several drives of the same model.