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I have several applications where I would like to improve the reliability of some existing computerised test equipment. One of the less reliable parts of a computer is the hard drive. I am considering using solid state (flash) disk
drives instead of conventional rotating disks. There are available from a number of sources ATA/IDE flash disks in sizes from 8 mega-bytes up to 900 mega-bytes. These devices are intended to interface to an IDE controller in the same way as a conventional drive, and even have the same form factor and mounting holes.
My application software (in use for several years) uses a DOS operating system. The software logs test results in a series of ASCII files, with new log files being started several times per day. There are no other files which are repeatedly written to or erased (excluding the DOS directory structure), and a moderately sized drive should hold several months worth of data before the older data is erased. One drive would hold the application, DOS, and all data files.
I was initially skeptical about whether this was feasible, but upon looking into the subject I discovered that with current flash write endurance and wear leveling techniques, the drives would appear to be able to last for several decades in this application. "Wear levelling" has a very strong effect on this calculation as only a very small percentage of the drive capacilty is written to per day.
My questions are:
1) Has anyone else used these drives in a similar (or any) application and,
2) do they have any comments they would like to share?
3) Is any OEM's particular wear leveling technique best (or worst) for this application?
I understand that using Windows would raise serious problems due to the swap file, but I am dealing with DOS, which doesn't have this problem.
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Michael Griffin
London, Ont. Canada
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drives instead of conventional rotating disks. There are available from a number of sources ATA/IDE flash disks in sizes from 8 mega-bytes up to 900 mega-bytes. These devices are intended to interface to an IDE controller in the same way as a conventional drive, and even have the same form factor and mounting holes.
My application software (in use for several years) uses a DOS operating system. The software logs test results in a series of ASCII files, with new log files being started several times per day. There are no other files which are repeatedly written to or erased (excluding the DOS directory structure), and a moderately sized drive should hold several months worth of data before the older data is erased. One drive would hold the application, DOS, and all data files.
I was initially skeptical about whether this was feasible, but upon looking into the subject I discovered that with current flash write endurance and wear leveling techniques, the drives would appear to be able to last for several decades in this application. "Wear levelling" has a very strong effect on this calculation as only a very small percentage of the drive capacilty is written to per day.
My questions are:
1) Has anyone else used these drives in a similar (or any) application and,
2) do they have any comments they would like to share?
3) Is any OEM's particular wear leveling technique best (or worst) for this application?
I understand that using Windows would raise serious problems due to the swap file, but I am dealing with DOS, which doesn't have this problem.
************************
Michael Griffin
London, Ont. Canada
************************