Bug #1527
closedextremely bad USB/msdos performance
Description
The performance for writing to msdosfs on an ehci usb device is
pathetic. I'm getting ~500KB/sec, while other OS can do at least 6MB.
the rsync process is most of the time in "iowait", "biows", "biord".
vmstat:
tin tout KB/t tps MB/s KB/t tps MB/s KB/t tps MB/s us ni
sy in id
8 680 60.86 56 3.33 0.00 0 0.00 10.00 2 0.02 3 0
5 0 93
7 400 64.00 2 0.12 0.00 0 0.00 16.00 1 0.02 1 0
5 0 94
10 415 64.00 2 0.12 0.00 0 0.00 0.00 0 0.00 3 0
5 0 92
9 528 0.00 0 0.00 0.00 0 0.00 16.00 2 0.03 2 0
3 0 95
9 541 64.00 4 0.25 0.00 0 0.00 16.00 86 1.34 2 0
6 0 92
10 399 0.00 0 0.00 0.00 0 0.00 16.00 138 2.16 4 0
6 0 90
8 546 64.00 2 0.12 0.00 0 0.00 16.00 4 0.06 7 0
8 0 85
7 509 37.75 89 3.28 0.00 0 0.00 15.68 37 0.57 3 0
8 0 89
10 545 0.00 0 0.00 0.00 0 0.00 16.00 131 2.05 3 0
8 0 89
1 104 4.00 1 0.00 0.00 0 0.00 16.00 40 0.62 5 0
7 0 87
2 226 48.00 86 4.03 0.00 0 0.00 14.29 7 0.10 4 0
6 0 90
102 100 64.00 2 0.12 0.00 0 0.00 16.00 110 1.72 2 0
5 0 93
126 102 64.00 2 0.12 0.00 0 0.00 16.00 37 0.58 3 0
6 0 91
72 103 64.00 1 0.06 0.00 0 0.00 13.29 124 1.61 0 0
4 0 95
42 98 64.00 1 0.06 0.00 0 0.00 0.00 0 0.00 1 0
3 0 96
176 225 45.40 86 3.81 0.00 0 0.00 16.00 2 0.03 4 0
6 0 90
136 104 19.43 84 1.59 0.00 0 0.00 16.00 11 0.17 7 0
8 0 85
70 121 0.00 0 0.00 0.00 0 0.00 16.00 26 0.41 1 0
10 0 89
26 100 64.00 5 0.31 0.00 0 0.00 16.00 140 2.19 2 0
5 0 93
2 219 56.79 91 5.05 0.00 0 0.00 15.79 58 0.89 3 0
6 0 91