How do I do something similar on a SD card ?
Like reformating the SD card, but at a lower-level to avoid the automatic wear-leveling.
Storage tools claims defragging you SD card increases performance, however they sell the product so they can claim whatever suits them.
Though there are other programs that claim it helps:
But here's some Storage Tools info anyway ;-)
Storage Tools Description
The most comprehensive storage card management solution, StorageTools is the first product to offer defragmentation functionality for Pocket PC devices, providing dramatic speed improvements by resolving file fragmentations.
With StorageTools you can get detailed device and file system information about your storage cards, analysis of file allocations (slack space) and fragmentation level.
StorageTools works with all media types available on PocketPC/Windows CE devices, including industry standards: ATA compliant memory cards, Compact Flash cards, MicroDrives, Secure Digital (SD) cards, MultiMedia Cards (MMC) and PCMCIA memory cards. You can format storage media with different file system and cluster size.
Scan tool diagnoses and repairs a variety of media problems. It performs several tests, checking everything from the boot sector to its physical surface. If StorageTools finds a problem, it notifies you before making repairs. Optionally allows making all necessary repairs automatically.
With StorageTools defragmenter you achieve maximum performance under Pocket PC/Windows CE with minimum effort! It includes the most professional and user-friendly features ever found in defragmentation software. You must eliminate fragmentation to eliminate the most basic performance bottleneck on your PocketPC device as you can on your powerful desktop computer.
The StorageTools includes full support for all storage/media cards even transparently encrypted volumes by Sentry 2020 for PocketPC, and includes options to choose FAT type and cluster size when formatting, plus the ability to create a backup FAT to improve storage reliability.
My understanding is that the current SDCARD spec does not include a TRIM command. Although I am not on the committee, Windows 7's support for TRIM will bring it to the attention of many engineers, and it's reasonable to expect that the command will show up in the SD spec within the next few years.
The OS uses the TRIM command to tell the flash device that a sector will not be read again until it is written. This tells the flash device that the sectors do not need to be copied from one page to another before the first page is erased. This can result in significantly improved performance and improved data privacy.
It would be nice if SD cards could give performance similar to SSDs. I don't see any fundamental reason why the small form factor could not support high-speed access. At the moment, though, if you want high-speed performance, you should use an SSD, not a SD card.