> From: Ivan Voras <[EMAIL PROTECTED]> > Date: Thu, 15 Feb 2007 19:12:40 +0100 > Sender: [EMAIL PROTECTED] > > Alexander Shikoff wrote: > > > umass0: vendor 0x1005 USB FLASH DRIVE, rev 2.00/1.00, addr 2 > > da0 at umass-sim0 bus 0 target 0 lun 0 > > da0: < USB FLASH DRIVE 34CH> Removable Direct Access SCSI-0 device > > da0: 40.000MB/s transfers > > da0: 3936MB (8060928 512 byte sectors: 255H 63S/T 501C) > > > > Writing to this device is very slooooow. > > > > Time taken to copy file of 1,4G is near 30 min. > > 1400/1800=0.77... which looks suspiciously like the rate I get while > copying over USB 1 port. What does "iostat 1" say while you're copying > the file?
Looks a lot like a new 4GB drive I bought. It is painfully slow. Here is the result of iostat: tty ad0 da0 pass0 cpu tin tout KB/t tps MB/s KB/t tps MB/s KB/t tps MB/s us ni sy in id 0 77 16.00 1 0.02 4.00 48 0.19 0.00 0 0.00 0 0 1 0 99 0 231 0.00 0 0.00 4.00 48 0.19 0.00 0 0.00 3 0 1 2 94 0 649 0.00 0 0.00 4.00 36 0.14 0.00 0 0.00 3 0 2 2 94 0 77 9.00 2 0.02 4.00 1 0.00 0.00 0 0.00 2 0 1 1 97 0 77 9.00 2 0.02 0.00 0 0.00 0.00 0 0.00 4 0 1 0 95 This is (obviously) from the end of the transfer. Transfer rate varies from .14 to .19 MB/s. While I have not one statistical analysis, it is clear that the mode is .14 and I'd guess the median is around 16 KB/s. (I calculated it over 20 samples in the middle of the transfer.) To say that this is dreadful is a major understatement, but I suspect it is an issue with the drive. I will try it on Windows and see it it works any better there. It might be crappy hardware. (At $30 for a 4GB drive, it was certainly cheap.) -- R. Kevin Oberman, Network Engineer Energy Sciences Network (ESnet) Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab) E-mail: [EMAIL PROTECTED] Phone: +1 510 486-8634 Key fingerprint:059B 2DDF 031C 9BA3 14A4 EADA 927D EBB3 987B 3751
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