Solutions to common problems in solid-state hard disks

Solid-State drives have not yet become mainstream, but many users have started using solid-state drives. For the application of solid-state hard disk, many friends may have such a live that doubt, the author for everyone carefully selected some people often ask the problem of solid-state hard disk, summarized as follows:

　　Q: Does Intel solid State hard Drive support hot-swappable?

A: No problem, fully supports the hot-swappable functionality defined by the SATA specification.

　Q: What process technology is used for Intel solid-state drives?

A: X18-m and x25-m are using the Intel 50nm MLC Flash, while X25-E is using 50nm SLC flash.

　　Q: When solid-state drives are filled, will performance drop?

A: That's a good question. For solid-state drives, performance is not related to how much data is stored. Whether empty or nearly full, the Flash loss Equalization management algorithm will work as usual.

Some common file systems, such as NTFS FAT32, may have degraded performance in the event of lack of space, but this is a software problem and is not associated with the use of solid-state storage. In the future, when a file system dedicated to solid-state drives is available, there may also be examples of how much hard disk storage data will affect performance.

　　Q: Which file system is best for solid-state drives?

A: None of the current file systems are optimized for solid-state drives. The computer industry has spent decades on optimizing rotating magnetic media storage, but the advent of solid-state drives has made these optimizations completely obsolete.

Fortunately, with the current solid-state drive speed, following the old file system requirements like a traditional hard drive to work, and will not have much damage. However, in the near future, we will certainly see the file system specifically designed for solid-state HDD optimization.

Microsoft will optimize SSD in Windows 7, such as disabling automatic disk defragmentation when using solid-state drives. One of my top concerns is the ATA trim command, which informs solid-state drives that a block is no longer in use and that SSD can reclaim its space and incorporate the next "loss balancing" operation.

In a Linux system, you can easily optimize a solid-state drive by disabling the kernel disk IO Scheduler module. Because there is no shift problem of the head read and write, the module reordering on the disk reads and writes does not make any sense to the solid-state hard disk, and even degrades the performance. Windows 7 is also expected to make the same improvements, but is not yet published.

　Q: What is the performance of SSD RAID 0? Can I implement RAID 0 within SSD?

A: Let's answer the second question first. Solid-State hard disk reading and writing itself is in parallel, the current Intel solid-state drive using 10 parallel channels to access flash memory, in a sense is equivalent to the built-in 10-way RAID 0.

The performance of a RAID 0 array with multiple solid-state drives is considerable, but it is important to ensure that the RAID controller is able to meet its requirements. Solid-State hard disks work in array mode with a large amount of data, and many RAID controllers may not have considered such speeds at all at design time.