I have done some quick testing. I formatted my Kingston DataTraveler G2
16GB drive as a FAT32, FAT32 (lba), EXT2, EXT3 disk one at a time and
tried copying over a file little over 1GB in size. I monitored the
actual disk operations with dstat.

What I have found is that the first 100 - 200MB for which the copying
speed is normal, does not actually get written to the disk. Up to the
point when Nautilus reports that 100 - 200MB is copied, dstat shows that
no writing takes place - which is (let's say) OK, because of the
caching. After this the operation starts to slow down and at this same
time data start to get written to the disk but with an incredibly slow
pace (< 100KB/s). If I do not cancel the operation Nautilus starts to
become unresponsive (dims out then back in -  because of compiz).

This is what dstat shows (this is for the test with EXT3 but others are
similar):

bote...@kryzisworx:~$ dstat -D sdb1
----total-cpu-usage---- --dsk/sdb1- -net/total- ---paging-- ---system--
usr sys idl wai hiq siq| read  writ| recv  send|  in   out | int   csw 
 14   5  64  16   0   0| 147B   32k|   0     0 |2485B   16k|1000  2158 
 12   4  83   0   0   0|   0     0 |2473B 2763B|   0     0 | 813  1504 
 10   4  85   0   0   0|   0     0 |1447B 1574B|   0     0 | 863  1561 
 12   3  84   0   0   0|   0     0 |5631B 4587B|   0     0 | 749  1463 
  5   4  89   0   1   0|   0     0 |4600B 4273B|   0     0 | 814  1255 
  8   7  83   2   0   0|   0     0 |2068B 3283B|   0     0 | 877  1733 
 11   4  84   0   0   0|   0     0 |3703B 4359B|   0     0 |1015  1751 
 14   6  41  37   2   0|8192B    0 |2015B 3422B|   0     0 |1235  2340 
 12  16  43  27   1   1|   0     0 |3336B 4627B|   0     0 |1595  2560 
 15  14  30  40   0   0|   0     0 |1398B 1492B|   0     0 |1456  2945 
 15  14  36  34   0   1|   0     0 |1267B  915B|   0     0 |1472  2756 
 15  15  39  29   0   1|4096B    0 | 569B  712B|   0     0 |1449  2680 
 15  18  26  40   0   0|   0     0 | 132B  168B|   0     0 |1550  2943 
 18  14  24  43   0   0|   0    52k| 673B  985B|   0     0 |1391  2520 
 11   8   2  79   1   0|   0  1920k| 144B  746B|   0     0 | 967  1751 
 11   5   0  83   1   0|   0  4224k|2211B 2500B|   0     0 |1085  1960 
  8   9   0  81   1   0|   0  4100k| 234B  504B|   0     0 |1178  2133 
 10   4   0  85   0   0|   0  2020k| 964B  778B|   0     0 | 866  1538 
  7   7   0  85   0   0|   0    28k| 764B 1410B|   0     0 | 785  1475 
  6   7  27  59   0   0|   0   568k|1354B 1696B|   0     0 | 963  1605 
 13   8   8  70   1   1|   0    52k|1579B 1925B|   0     0 |1236  2144 
 13   4   0  83   0   0|   0    56k|1811B 3758B|   0     0 | 829  1473 
 10   5   0  84   1   1|   0    80k|1700B 3975B|  32k   80k| 900  1508 
----total-cpu-usage---- --dsk/sdb1- -net/total- ---paging-- ---system--
usr sys idl wai hiq siq| read  writ| recv  send|  in   out | int   csw 
  9   7   0  84   0   0|   0    88k|2122B 3456B|   0     0 | 953  1539 
  8   7   0  84   0   0|   0    56k| 546B  731B|   0     0 | 845  1478 
 11   8   0  80   0   0|   0    40k|  12k   17k|   0     0 |1018  1631 
 13   3   0  83   0   0|   0    60k|4218B   12k|   0     0 |1027  1861 
 12   3   0  84   1   0|   0    28k|1230B 3793B|   0     0 | 835  1534 
 13   5   0  82   0   0|  16k   28k| 277B 1018B|   0     0 | 925  1702 
 11   4  25  61   0   0|   0   200k|1316B 2976B|   0     0 | 850  1475 
 11   6   3  80   1   1|   0    36k|1485B 3581B|   0     0 | 863  1566 
 11   6   0  82   0   0|   0    60k|2372B 4931B|  32k    0 | 913  1399 
 10   6   0  85   1   0|   0    40k| 283B  873B|   0     0 | 871  1475 
 15   3   0  82   0   0|  96k   20k|3311B  374B|   0     0 | 933  1697 
 10   2   0  86   1   0|   0    28k| 196B  250B|   0     0 | 762  1414 
 12   5   0  83   0   0|   0    24k|2192B 3740B|   0     0 | 887  1699 
 16   3   0  81   0   0|   0    36k|1864B 2708B|   0     0 | 943  1743 
 16   4   0  79   1   0|   0    92k|1986B 3804B|   0     0 | 982  1772 
 12   6   0  82   0   0| 128k   52k|1181B 2004B|   0    28k|1048  1744 
 12   7   0  81   0   0|   0    64k|2174B 2626B|  32k    0 | 829  1395 
  9   5   0  86   0   0|   0   116k|2371B 2166B|   0     0 | 859  1642 
 12   5  20  64   1   0|   0   148k|1583B 2729B|   0     0 |1061  1801 
 11   3   0  86   0   0|   0   100k| 320B  293B|   0     0 | 790  1427 
 14   7   0  79   0   0|   0   912k| 670B 1285B|   0     0 | 878  1749 
 12   6   0  80   1   0|1784k   20k| 451B 1504B|   0     0 |1024  2260 ^C
bote...@kryzisworx:~$

-- 
file transfers on USB disk are very slow
https://bugs.launchpad.net/bugs/197762
You received this bug notification because you are a member of Ubuntu
Desktop Bugs, which is a bug assignee.

-- 
desktop-bugs mailing list
desktop-bugs@lists.ubuntu.com
https://lists.ubuntu.com/mailman/listinfo/desktop-bugs

Reply via email to