![]() However some drives will not immediately remap such sectors when written instead the drive will first attempt to write to the problem sector and if the write operation is successful then the sector will be marked good (in this case, the "Reallocation Event Count" (0xC4) will not be increased). Read errors on a sector will not remap the sector immediately (since the correct value cannot be read and so the value to remap is not known, and also it might become readable later) instead, the drive firmware remembers that the sector needs to be remapped, and will remap it the next time it's written. If an unstable sector is subsequently read successfully, the sector is remapped and this value is decreased. If sequential access speed is critical, the remapped sectors can be manually marked as bad blocks in the file system in order to prevent their use.Ĭount of "unstable" sectors (waiting to be remapped, because of unrecoverable read errors). ![]() As the count of reallocated sectors increases, the read/write speed tends to become worse because the drive head is forced to seek to the reserved area whenever a remap is accessed. While primarily used as a metric of the life expectancy of the drive, this number also affects performance. This allows a drive with bad sectors to continue operation however, a drive which has had any reallocations at all is significantly more likely to fail in the near future. Thus, the higher the attribute value, the more sectors the drive has had to reallocate. The raw value normally represents a count of the bad sectors that have been found and remapped. This process is also known as remapping, and reallocated sectors are called "remaps". When the hard drive finds a read/write/verification error, it marks that sector as "reallocated" and transfers data to a special reserved area (spare area). To help explain what the numbers mean here is an extract from the Wikipedia S.M.A.R.T.
0 Comments
Leave a Reply. |