Life above the horizon

Cruzer Crossfire 1.0GB -This is my newly bought 1GB thumbdrive at sgd23. Isn't beautiful?




What is more beautiful is that it can support Windows Vista new feature - ReadyBoost!
So what is this ReadyBoost about? ReadyBoost is a technology built into Windows Vista that caches disk reads onto a flash memory device. It can work with USB memory keys, flash memory cards, such as SD and CompactFlash, and other types of flash devices. It caches all types of file reads, not just the working set, nor just DLL's or other persistent operating system data.

ReadyBoost does not cache file writes—it's a write-through cache. That way, you never lose any precious data that's meant to be written to a hard drive. After all, a flash memory key can get yanked out of a system at any time. The cache itself is encrypted using AES-128 encryption, so no one can steal your flash memory key and casually browse through the cache file to see what you've been doing.

The minimum requirements for a USB memory device to be ReadyBoost capable is 2.5MB/sec for 4K random access reads and 1.5MB/sec for 512K random writes—and that rate has to be achieved across the whole flash memory space. When you plug a USB memory device into the system, Vista actually does a performance check to see if the device meets the standard. Vista won't allow you to use a device it thinks will slow the system down. Note that USB hard drives won't work.

Microsoft's general recommendation for maximum benefit from ReadyBoost is to match the capacity of the flash device to the size of your system's main memory. So if you have 2GB of system RAM, use a 2GB USB key. Note that some benefit is gained from using any flash device, and the capacities supported for ReadyBoost range from 256MB to 4GB.

So can it really speed up the system and how much?

"Well, that depends. On average, a RANDOM 4K read from flash is about 10x faster than from HDD. Now, how does that translate to end-user perf? Under memory pressure and heavy disk activity, the system is much more responsive; on a 4GB machine with few applications running, the ReadyBoost effect is much less noticable", Matt Ayers, Program Manager of Microsoft Windows Client Performance group, says.