The difference between SSDs and traditional hard drives go well beyond energy savings and fast I/O rates. There are some fundamental ways flash chips store data, which makes regular defrag and other drive optimization techniques that operating systems employ unsuitable for SSDs.
The Windows 7 team says not to worry, they have it covered….
Windows 7 will disable disk defragmentation on SSD system drives. Because SSDs perform extremely well on random read operations, defragmenting files isn’t helpful enough to warrant the added disk writing defragmentation produces…
By default, Windows 7 will disable Superfetch, ReadyBoost, as well as boot and application launch prefetching on SSDs with good random read, random write and flush performance. These technologies were all designed to improve performance on traditional HDDs, where random read performance could easily be a major bottleneck. See the FAQ section for more details.
Since SSDs tend to perform at their best when the operating system’s partitions are created with the SSD’s alignment needs in mind, all of the partition-creating tools in Windows 7 place newly created partitions with the appropriate alignment.
Another way they optimized Windows 7 for SSDs is with a process called Trim. They explain:
In addition to the above, Microsoft and SSD manufacturers are adopting the Trim operation. In Windows 7, if an SSD reports it supports the Trim attribute of the ATA protocol’s Data Set Management command, the NTFS file system will request the ATA driver to issue the new operation to the device when files are deleted and it is safe to erase the SSD pages backing the files. With this information, an SSD can plan to erase the relevant blocks opportunistically (and lazily) in the hope that subsequent writes will not require a blocking erase operation since erased pages are available for reuse.
As an added benefit, the Trim operation can help SSDs reduce wear by eliminating the need for many merge operations to occur. As an example, consider a single 128 KB SSD block that contained a 128 KB file. If the file is deleted and a Trim operation is requested, then the SSD can avoid having to mix bytes from the SSD block with any other bytes that are subsequently written to that block. This reduces wear.
Now, if they can do something about the huge price premium over regular hard drives, then we’re in business. Read more about Windows 7 SSD support here.
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