If you have a slow hard disk, ReadyBoost (see instructions for setting up ReadyBoost) offers a significant performance boost. In my tests, adding a standard USB flash drive to a computer with a WEI disk rating of 3.7 reduced startup time about 30%. Adding ReadyBoost to computers with a WEI disk rating of 5.0 or higher did not improve startup time, but might slightly improve performance after startup. Future “Enhanded for ReadyBoost” flash drives will probably make more of a difference.
Conclusion: Â If you have an unused flash drive, plug it in and set it up for ReadyBoost. It won’t hurt. If you have a computer with a WEI disk rating of less than 4.0, adding a ReadyBoost flash drive offers good bang-for-the-buck. If you have a computer with a WEI disk rating of more than 5.0, ReadyBoost still won’t hurt, but it probably won’t give you a noticable improvement.
Read on for the technical details.
ReadyBoost creates a disk cache file (ReadyBoost.sfcache) of the size you specify on flash memory, which offers better performance for random reads than hard disks. The contents of this file are encrypted so there’s no easy way for me to see exactly what’s cached, but Vista uses the “SmartFetch” algorithm to figure out what should be stored there. It reads from the cache whenever it thinks it’ll be faster than the hard disk. The cache is only a copy, so you can remove it from the computer at any time without losing data.
I tested ReadyBoost with three computers and two flash drives. The computers:
- Dell Latitude D600. WEI disk rating of 3.7. This is a four-year-old laptop with a 4200 RPM hard disk.
- Dell Latitude D820. WEI disk rating of 5.1. This is a nine-month-old laptop with a 7200 RPM hard disk.
- Systemax generic desktop. WEI disk rating of 5.5. This is a three-month-old fast desktop with a 7200 RPM hard disk.
The flash drives:
- Lexar JumpDrive 1GB. This drive reduced startup time by 30% in the older Dell D600 laptop, from 59.3 seconds to 39.8 seconds. This laptop has a slow (4500 RPM) hard disk. On my faster laptop (with a 7200 RPM hard disk) it didn’t improve performance, and the activity light hardly lit during startup. It was accessed after startup on all computers, so no doubt it increased performance by a small amount in general usage.
- 2GB Kingston 50x CF card. This card only passed ReadyBoost performance tests on the desktop computer when connected to the internal memory card reader. When connected via a USB 2.0 memory card reader, it was too slow. Unfortunately, it didn’t improve startup times on the desktop–probably because the desktop has a fast hard disk (7200 RPM) and because startup is mostly sequential reads, rather than the random reads that ReadyBoost is optimized for.
I tested each scenario three or more times (until results were consistent). When first attaching the ReadyBoost drive, I waited for Vista to pre-load the cache by watching the activity light and waiting more than ten minutes. Then, I rebooted a couple of times to make sure the SuperFetch algorithm knew which files needed to be loaded, and waited for the drive to be updated (the activity light flashed regularly).
Here are the startup times for the D600, the only computer that showed performance improvements:
- D600 without cache (seconds): 60.0, 59.3, 59.3
- D600 startup times with cache (seconds): 39.7, 39.8, 39.8
If you can get your hands on an â€œEnhanced for Windows ReadyBoostâ€ flash drive, you’ll get better results. Flash drives are always slower than hard disk for sequential reads, so ReadyBoost only uses flash drives for random reads, where hard disks are slow because of the time required to move the read head around. No doubt, flash drives that are designed specifically for ReadyBoost will be optimized for random reads. This is in distinct contrast to my Kingston 50x CF card, which is optimized for sequential writes–the most important factor for digital photography.
Please leave comments describing your experiences with ReadyBoost.