Comment 222 for bug 197762

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):

boteeka@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
boteeka@kryzisworx:~$