There is a lot of talk on Readyboost on the web, but the details are lacking. After googling a bit, here's my take:
1) FAT or FAT32 or NTFS?
Though FAT and FAT32 use less CPU overhead, I thought that FAT would be fastest. Turns out to be not so... I guess it's because today's CPUs are so fast that the CPU overhead is nothing at all. Here're some experimenter data:
Test run #1 (without thumbdrive):
* Average boot time: 1:10m ~ 70s
Test run #2 (FAT32 formatted, 1840MB ReadyBoost swap file):
* Average boot time: 1:13m ~ 73s
Test run #3 (NTFS formatted, 1840MB ReadyBoost swap file):
* Average boot time: 1:05m ~ 65s
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2) Format the USB drive at what sector or cluster size?
This is simple. If you have tons of small files, cluster size is an issue, since the smallest files which can be generated and stored is the size of the cluster. So if you have a 4KB cluster size, a 1KB file in fact would still take 4KB. Since Vista uses ONE HUGE FILE, just the default cluster size would be fine. Or any cluster size would be fine. The one detail I haven't worked out is `whether USB drives have a native cluster size'. Anybody can tell me this? I'd be grateful.
3) Which USB flash drive works?
I used the Imation Thumbdrive Micro 1GB, and it worked like a charm.
Discussion thread here, almost everything covered!