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Old 30th August 2017
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jggimi jggimi is offline
More noise than signal
Join Date: May 2008
Location: USA
Posts: 6,423

Originally Posted by ucharfli View Post
..If necessary I can use stable OpenBSD and install it...
There have been no significant operational changes to disk device management between 6.1-release and -current, which will become 6.2-release later this year. (There are never any developmental changes between a -release and its -stable branch, all -stable and errata patches are for break/fix only.)
Can we explain this place a little better?
The TRIM (for ATA drives) and UNMAP (for SCSI drives) commands an OS may send to a disk drive controller are to inform the drive that a range of sectors are no longer in use. The purpose of TRIM or UNMAP (same thing) is to mitigate performance degradation by reducing the number of overwrite operations the drive must perform, on future writes to those sectors. This is because on solid state media, an overwrite may take longer, and possibly produce more wear on the drive.

During development and testing, two approaches were tested. TRIM of individual sectors, and TRIM of sector ranges. Both produced performance degradations of the disk drive, larger than any degradation that could be caused by running without TRIM at all. A third option, TRIM of multiple sector ranges, may provide acceptable performance results, but this form of TRIM will require significant development and is currently deferred.
Can I use it without making any configuration?
Yes, you may use solid state drives as if they are any other kind of disk drive. Overwrites may take longer than an initial write, but the drive will operate faster than if it were using either of the TRIM operations that were developed, tested, and discarded.

Last edited by jggimi; 30th August 2017 at 04:42 PM. Reason: clarity
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