Baltix

  1. Bug #50741
  2. Activity log

Activity log for bug #50741

Date Who What changed Old value New value Message
2006-06-23 04:12:38 Erik de Castro Lopo bug added bug
2006-06-23 04:15:13 Erik de Castro Lopo description Runing the above kernel on a Dell Latitude X1 laptop. Disk writes are very much slower with this kernel than with linux-image-2.6.15-23-686. I have a test program which does a large amount of reading and writing of files. On the -23 kernel this program runs in 16-18 seconds. On the -25 kernel the same binary takes from 1 -4 minutes. The machine is not doing much else at the time. Here's the dstat output from the -23 kernel (write throughput about a Meg a second) ----total-cpu-usage---- -disk/total -net/total- ---paging-- ---system-- usr sys idl wai hiq siq|_read write|_recv _send|__in_ _out_|_int_ _csw_ 27 16 52 5 1 0| 111k 55k| 0 0 | 0 0 |1014 125 0 0 100 0 0 0| 0 0 |1364B 3230B| 0 0 |1021 61 43 29 29 0 0 0| 0 580k|1306B 3452B| 0 0 |1076 307 25 13 38 25 0 0| 0 1160k| 956B 5238B| 0 0 |1151 458 10 30 20 30 0 10| 0 1372k|1164B 6426B| 0 0 |1143 452 29 14 29 29 0 0| 0 1136k| 714B 4972B| 0 0 |1108 401 22 11 33 22 11 0|4096B 1224k| 918B 5894B| 0 0 |1155 480 22 22 33 22 0 0| 0 1356k|1377B 7408B| 0 0 |1164 490 27 9 27 27 9 0| 0 1424k| 950B 5588B| 0 0 |1177 665 29 14 29 29 0 0| 0 1216k|1020B 5288B| 0 0 |1155 508 25 25 38 13 0 0| 0 1100k| 816B 5206B| 0 0 |1154 439 22 22 33 22 0 0|4096B 1264k|1148B 5620B| 0 0 |1151 440 36 36 18 9 0 0| 0 1056k|1610B 8432B| 0 0 |1154 452 14 14 43 29 0 0| 0 1104k| 714B 4590B| 0 0 |1122 496 22 22 33 22 0 0| 0 1304k|1020B 6566B| 0 0 |1155 511 22 11 22 33 11 0| 0 1300k|1170B 3910B| 0 0 |1141 408 25 25 25 25 0 0| 0 980k|1402B 6814B| 0 0 |1133 432 11 33 33 22 0 0|4096B 1204k|1224B 6444B| 0 0 |1136 448 25 13 38 25 0 0| 0 1152k|1456B 5898B| 0 0 |1160 495 30 20 30 20 0 0| 0 1280k|1358B 8108B| 0 0 |1146 496 43 14 43 0 0 0| 0 348k|2303B 5166B| 0 0 |1098 206 And now the -25 output (about 1/10th the disk throughput): ----total-cpu-usage---- -disk/total -net/total- ---paging-- ---system-- usr sys idl wai hiq siq|_read write|_recv _send|__in_ _out_|_int_ _csw_ 0 0 50 50 0 0| 0 136k| 166B 666B| 0 0 | 338 57 33 33 0 33 0 0| 0 60k| 448B 634B| 0 0 | 327 42 0 0 100 0 0 0| 0 124k| 166B 748B| 0 0 | 332 59 0 0 50 50 0 0| 0 40k| 166B 634B| 0 0 | 363 42 0 50 50 0 0 0| 0 140k| 246B 634B| 0 0 | 355 68 33 0 33 33 0 0| 0 84k| 236B 956B| 0 0 | 333 46 0 33 67 0 0 0| 0 96k| 344B 694B| 0 0 | 286 59 100 0 0 0 0 0| 0 80k| 166B 666B| 0 0 | 339 47 0 0 50 50 0 0| 0 68k| 294B 700B| 0 0 | 336 48 0 0 100 0 0 0| 0 132k| 230B 634B| 0 0 | 275 55 0 0 50 50 0 0| 0 100k| 294B 634B| 0 0 | 285 59 0 33 33 33 0 0| 0 72k| 470B 634B| 0 0 | 306 50 0 0 0 100 0 0| 0 88k| 358B 1242B| 0 0 | 349 55 50 0 50 0 0 0| 0 80k| 358B 650B| 0 0 | 324 47 33 0 33 33 0 0| 0 112k| 102B 666B| 0 0 | 356 63 0 50 50 0 0 0| 0 72k| 483B 1070B| 0 0 | 327 32 0 0 50 50 0 0| 0 120k| 306B 650B| 0 0 | 353 62 The hdparm settings are identical under both kernels: /dev/hda: multcount = 0 (off) IO_support = 0 (default 16-bit) unmaskirq = 0 (off) using_dma = 1 (on) keepsettings = 0 (off) readonly = 0 (off) readahead = 256 (on) geometry = 16383/255/63, sectors = 117210240, start = 0 I can't debug this any further, but happy to do testing if someone has an idea. Note: the original reporter indicated the bug was in package 'linux-image-2.6.15-25-686'; however, that package was not published in Baltix. Runing the above kernel on a Dell Latitude X1 laptop. Disk writes are very much slower with this kernel than with linux-image-2.6.15-23-686. I have a test program which does a large amount of reading and writing of files. On the -23 kernel this program runs in 16-18 seconds. On the -25 kernel the same binary takes from 1 -4 minutes. The machine is not doing much else at the time. Here's the dstat output from the -23 kernel (write throughput about a Meg a second) ----total-cpu-usage---- -disk/total -net/total- ---paging-- ---system-- usr sys idl wai hiq siq|_read write|_recv _send|__in_ _out_|_int_ _csw_ 27 16 52 5 1 0| 111k 55k| 0 0 | 0 0 |1014 125 0 0 100 0 0 0| 0 0 |1364B 3230B| 0 0 |1021 61 43 29 29 0 0 0| 0 580k|1306B 3452B| 0 0 |1076 307 25 13 38 25 0 0| 0 1160k| 956B 5238B| 0 0 |1151 458 10 30 20 30 0 10| 0 1372k|1164B 6426B| 0 0 |1143 452 29 14 29 29 0 0| 0 1136k| 714B 4972B| 0 0 |1108 401 22 11 33 22 11 0|4096B 1224k| 918B 5894B| 0 0 |1155 480 22 22 33 22 0 0| 0 1356k|1377B 7408B| 0 0 |1164 490 27 9 27 27 9 0| 0 1424k| 950B 5588B| 0 0 |1177 665 29 14 29 29 0 0| 0 1216k|1020B 5288B| 0 0 |1155 508 25 25 38 13 0 0| 0 1100k| 816B 5206B| 0 0 |1154 439 22 22 33 22 0 0|4096B 1264k|1148B 5620B| 0 0 |1151 440 36 36 18 9 0 0| 0 1056k|1610B 8432B| 0 0 |1154 452 14 14 43 29 0 0| 0 1104k| 714B 4590B| 0 0 |1122 496 22 22 33 22 0 0| 0 1304k|1020B 6566B| 0 0 |1155 511 22 11 22 33 11 0| 0 1300k|1170B 3910B| 0 0 |1141 408 25 25 25 25 0 0| 0 980k|1402B 6814B| 0 0 |1133 432 11 33 33 22 0 0|4096B 1204k|1224B 6444B| 0 0 |1136 448 25 13 38 25 0 0| 0 1152k|1456B 5898B| 0 0 |1160 495 30 20 30 20 0 0| 0 1280k|1358B 8108B| 0 0 |1146 496 43 14 43 0 0 0| 0 348k|2303B 5166B| 0 0 |1098 206 And now the -25 output (about 1/10th the disk throughput): ----total-cpu-usage---- -disk/total -net/total- ---paging-- ---system-- usr sys idl wai hiq siq|_read write|_recv _send|__in_ _out_|_int_ _csw_ 0 0 50 50 0 0| 0 136k| 166B 666B| 0 0 | 338 57 33 33 0 33 0 0| 0 60k| 448B 634B| 0 0 | 327 42 0 0 100 0 0 0| 0 124k| 166B 748B| 0 0 | 332 59 0 0 50 50 0 0| 0 40k| 166B 634B| 0 0 | 363 42 0 50 50 0 0 0| 0 140k| 246B 634B| 0 0 | 355 68 33 0 33 33 0 0| 0 84k| 236B 956B| 0 0 | 333 46 0 33 67 0 0 0| 0 96k| 344B 694B| 0 0 | 286 59 100 0 0 0 0 0| 0 80k| 166B 666B| 0 0 | 339 47 0 0 50 50 0 0| 0 68k| 294B 700B| 0 0 | 336 48 0 0 100 0 0 0| 0 132k| 230B 634B| 0 0 | 275 55 0 0 50 50 0 0| 0 100k| 294B 634B| 0 0 | 285 59 0 33 33 33 0 0| 0 72k| 470B 634B| 0 0 | 306 50 0 0 0 100 0 0| 0 88k| 358B 1242B| 0 0 | 349 55 50 0 50 0 0 0| 0 80k| 358B 650B| 0 0 | 324 47 33 0 33 33 0 0| 0 112k| 102B 666B| 0 0 | 356 63 0 50 50 0 0 0| 0 72k| 483B 1070B| 0 0 | 327 32 0 0 50 50 0 0| 0 120k| 306B 650B| 0 0 | 353 62 The hdparm settings are identical under both kernels: /dev/hda: multcount = 0 (off) IO_support = 0 (default 16-bit) unmaskirq = 0 (off) using_dma = 1 (on) keepsettings = 0 (off) readonly = 0 (off) readahead = 256 (on) geometry = 16383/255/63, sectors = 117210240, start = 0 I can't debug this any further, but happy to do testing if someone has an idea. Note: the original reporter indicated the bug was in package 'linux-image-2.6.15-25-686'; however, that package was not published in Baltix.
2006-06-23 04:15:13 Erik de Castro Lopo title Slow disk writes Slow disk writes (ubuntu kernel)
2006-06-23 04:52:02 Erik de Castro Lopo bug assigned to Ubuntu
2006-06-23 04:53:14 Erik de Castro Lopo None: status Unconfirmed Rejected
2006-06-23 04:53:14 Erik de Castro Lopo None: statusexplanation
2006-12-20 02:37:35 Andrew Ash None: status Unconfirmed Rejected
2006-12-20 02:37:35 Andrew Ash None: statusexplanation Glad you found the fix. If it becomes a problem again, let us know and we'll see if we can help. Thanks for your contribution to Ubuntu.