During the last Dell’s “Days of Deals” I’ve bought myself a new USB flash drive. My old but good Patriod 8Gb started to fall apart and there was a need for a more rugged flash disk. Also needed some more storage to move all the files I have for home and work. Even though it claims amazing 200x (what is their 1x?) speed my benchmarks are as follows.
hdparm -tT /dev/sdf
Timing cached reads: 5326 MB in 2.00 seconds = 2663.99 MB/sec
Timing buffered disk reads: 68 MB in 3.02 seconds = 22.53 MB/sec
Write speeds (for ~512Mb):
dd if=/dev/zero of=/dev/sdf bs=1024 count=500000
512000000 bytes (512 MB) copied, 11.5051 s, 44.5 MB/s
dd if=/dev/zero of=/dev/sdf bs=2048 count=250000
512000000 bytes (512 MB) copied, 14.6622 s, 34.9 MB/s
dd if=/dev/zero of=/dev/sdf bs=4096 count=125000
512000000 bytes (512 MB) copied, 27.8725 s, 18.4 MB/s
dd if=/dev/zero of=/dev/sdf bs=8192 count=65000
532480000 bytes (532 MB) copied, 13.6919 s, 38.9 MB/s
So format your disk either 1Kb or 8Kb blocks to achieve maximum speed of about 40MBytes/s write speed and read speed around 50Mbps.
Benchmarks were performed on Kubuntu 9.04 AMD64 edition. Note: benchmarks are not really accurate (as OS caching might be involved here and there) but give clear guidance about which block sizes I should avoid with this drive.