git checkout f722406faae2d073cc1d01063d1123c35425939e Previous HEAD position was ade1335... xfs: ensure btree root split sets blkno correctly HEAD is now at f722406... Linux 3.10-rc1 ls -a /kernel-tests/run-queue/kvm/x86_64-nfsroot/xfs:for-next:f722406faae2d073cc1d01063d1123c35425939e:bisect-mm 2013-06-15-06:07:10 f722406faae2d073cc1d01063d1123c35425939e reuse /kernel/x86_64-nfsroot/f722406faae2d073cc1d01063d1123c35425939e/vmlinuz-3.10.0-rc1 2013-06-15-06:07:10 detecting boot state . 6 29 43 76 87 92. 98 100 SUCCESS bisect: good commit f722406faae2d073cc1d01063d1123c35425939e git bisect start ade1335afef556df6538eb02e8c0dc91fbd9cc37 f722406faae2d073cc1d01063d1123c35425939e -- Previous HEAD position was f722406... Linux 3.10-rc1 HEAD is now at c1be5a5... Linux 3.9 Bisecting: 15 revisions left to test after this (roughly 4 steps) [d4c712bcf26a25c2b67c90e44e0b74c7993b5334] xfs: fully initialise temp leaf in xfs_attr3_leaf_compact git bisect run /c/kernel-tests/bisect-test-boot-failure.sh /home/wfg/usb/obj-bisect running /c/kernel-tests/bisect-test-boot-failure.sh /home/wfg/usb/obj-bisect ls -a /kernel-tests/run-queue/kvm/x86_64-nfsroot/xfs:for-next:d4c712bcf26a25c2b67c90e44e0b74c7993b5334:bisect-mm 2013-06-15-06:12:23 d4c712bcf26a25c2b67c90e44e0b74c7993b5334 compiling 306 real 1460 user 117 sys 514.12% cpu x86_64-nfsroot 2013-06-15-06:18:08 detecting boot state 3.10.0-rc1-00015-gd4c712b....... TEST FAILURE dmesg-kvm-stoakley-4592-20130615062107-3.10.0-rc1-00015-gd4c712b-18 dmesg-kvm-stoakley-5117-20130615062103-3.10.0-rc1-00015-gd4c712b-18 dmesg-kvm-stoakley-3678-20130615062113-3.10.0-rc1-00015-gd4c712b-18 dmesg-kvm-vp-15260-20130615062320-3.10.0-rc1-00015-gd4c712b-18 dmesg-kvm-vp-40909-20130615062324-3.10.0-rc1-00015-gd4c712b-18 dmesg-kvm-bens-7956-20130615062039-3.10.0-rc1-00015-gd4c712b-18 dmesg-kvm-stoakley-4282-20130615062122-3.10.0-rc1-00015-gd4c712b-18 dmesg-kvm-stoakley-4481-20130615062121-3.10.0-rc1-00015-gd4c712b-18 dmesg-kvm-vp-14836-20130615062330-3.10.0-rc1-00015-gd4c712b-18 dmesg-kvm-vp-15869-20130615062330-3.10.0-rc1-00015-gd4c712b-18 dmesg-kvm-vp-29296-20130615062332-3.10.0-rc1-00015-gd4c712b-18 dmesg-kvm-vp-32856-20130615062332-3.10.0-rc1-00015-gd4c712b-18 dmesg-kvm-vp-36600-20130615062331-3.10.0-rc1-00015-gd4c712b-18 Bisecting: 7 revisions left to test after this (roughly 3 steps) [b38958d715316031fe9ea0cc6c22043072a55f49] xfs: xfs_attr_shortform_allfit() does not handle attr3 format. running /c/kernel-tests/bisect-test-boot-failure.sh /home/wfg/usb/obj-bisect ls -a /kernel-tests/run-queue/kvm/x86_64-nfsroot/xfs:for-next:b38958d715316031fe9ea0cc6c22043072a55f49:bisect-mm 2013-06-15-06:21:39 b38958d715316031fe9ea0cc6c22043072a55f49 compiling 153 real 1461 user 121 sys 1031.10% cpu x86_64-nfsroot 2013-06-15-06:24:25 detecting boot state 3.10.0-rc1-00007-gb38958d....... TEST FAILURE dmesg-kvm-vp-13915-20130615062935-3.10.0-rc1-00007-gb38958d-19 dmesg-kvm-vp-20632-20130615062942-3.10.0-rc1-00007-gb38958d-19 dmesg-kvm-vp-30221-20130615062951-3.10.0-rc1-00007-gb38958d-19 dmesg-kvm-vp-31620-20130615062947-3.10.0-rc1-00007-gb38958d-19 dmesg-kvm-vp-28937-20130615062951-3.10.0-rc1-00007-gb38958d-19 Bisecting: 3 revisions left to test after this (roughly 2 steps) [28ca489c63e9aceed8801d2f82d731b3c9aa50f5] xfs: fix rounding in xfs_free_file_space running /c/kernel-tests/bisect-test-boot-failure.sh /home/wfg/usb/obj-bisect ls -a /kernel-tests/run-queue/kvm/x86_64-nfsroot/xfs:for-next:28ca489c63e9aceed8801d2f82d731b3c9aa50f5:bisect-mm 2013-06-15-06:27:57 28ca489c63e9aceed8801d2f82d731b3c9aa50f5 compiling 175 real 1469 user 124 sys 906.68% cpu x86_64-nfsroot 2013-06-15-06:31:08 detecting boot state 3.10.0-rc1-00003-g28ca489....... 1 TEST FAILURE dmesg-kvm-vp-12443-20130615063635-3.10.0-rc1-00003-g28ca489-20 dmesg-kvm-vp-13138-20130615063641-3.10.0-rc1-00003-g28ca489-20 dmesg-kvm-vp-20632-20130615063639-3.10.0-rc1-00003-g28ca489-20 dmesg-kvm-vp-20928-20130615063640-3.10.0-rc1-00003-g28ca489-20 dmesg-kvm-vp-22127-20130615063641-3.10.0-rc1-00003-g28ca489-20 dmesg-kvm-vp-22338-20130615063639-3.10.0-rc1-00003-g28ca489-20 dmesg-kvm-vp-29296-20130615063641-3.10.0-rc1-00003-g28ca489-20 dmesg-kvm-vp-41632-20130615063639-3.10.0-rc1-00003-g28ca489-20 dmesg-kvm-vp-19031-20130615063643-3.10.0-rc1-00003-g28ca489-20 Bisecting: 0 revisions left to test after this (roughly 1 step) [49b137cbbcc836ef231866c137d24f42c42bb483] xfs: fix sub-page blocksize data integrity writes running /c/kernel-tests/bisect-test-boot-failure.sh /home/wfg/usb/obj-bisect ls -a /kernel-tests/run-queue/kvm/x86_64-nfsroot/xfs:for-next:49b137cbbcc836ef231866c137d24f42c42bb483:bisect-mm 2013-06-15-06:35:10 49b137cbbcc836ef231866c137d24f42c42bb483 compiling 139 real 1460 user 122 sys 1131.60% cpu x86_64-nfsroot 2013-06-15-06:37:41 detecting boot state 3.10.0-rc1-00002-g49b137c....... TEST FAILURE dmesg-kvm-vp-13255-20130615064304-3.10.0-rc1-00002-g49b137c-21 Bisecting: 0 revisions left to test after this (roughly 0 steps) [211d022c43cac3aecbe967fcaf9b10156bfa63ad] xfs: Avoid pathological backwards allocation running /c/kernel-tests/bisect-test-boot-failure.sh /home/wfg/usb/obj-bisect ls -a /kernel-tests/run-queue/kvm/x86_64-nfsroot/xfs:for-next:211d022c43cac3aecbe967fcaf9b10156bfa63ad:bisect-mm 2013-06-15-06:41:12 211d022c43cac3aecbe967fcaf9b10156bfa63ad compiling 143 real 1482 user 132 sys 1128.17% cpu x86_64-nfsroot 2013-06-15-06:43:46 detecting boot state 3.10.0-rc1-00001-g211d022....... TEST FAILURE dmesg-kvm-stoakley-4481-20130615064637-3.10.0-rc1-00001-g211d022-22 dmesg-kvm-stoakley-4683-20130615064639-3.10.0-rc1-00001-g211d022-22 dmesg-kvm-stoakley-3678-20130615064644-3.10.0-rc1-00001-g211d022-22 211d022c43cac3aecbe967fcaf9b10156bfa63ad is the first bad commit commit 211d022c43cac3aecbe967fcaf9b10156bfa63ad Author: Jan Kara Date: Thu Apr 11 22:09:56 2013 +0200 xfs: Avoid pathological backwards allocation Writing a large file using direct IO in 16 MB chunks sometimes results in a pathological allocation pattern where 16 MB chunks of large free extent are allocated to a file in a reversed order. So extents of a file look for example as: ext logical physical expected length flags 0 0 13 4550656 1 4550656 188136807 4550668 12562432 2 17113088 200699240 200699238 622592 3 17735680 182046055 201321831 4096 4 17739776 182041959 182050150 4096 5 17743872 182037863 182046054 4096 6 17747968 182033767 182041958 4096 7 17752064 182029671 182037862 4096 ... 6757 45400064 154381644 154389835 4096 6758 45404160 154377548 154385739 4096 6759 45408256 252951571 154381643 73728 eof This happens because XFS_ALLOCTYPE_THIS_BNO allocation fails (the last extent in the file cannot be further extended) so we fall back to XFS_ALLOCTYPE_NEAR_BNO allocation which picks end of a large free extent as the best place to continue the file. Since the chunk at the end of the free extent again cannot be further extended, this behavior repeats until the whole free extent is consumed in a reversed order. For data allocations this backward allocation isn't beneficial so make xfs_alloc_compute_diff() pick start of a free extent instead of its end for them. That avoids the backward allocation pattern. See thread at http://oss.sgi.com/archives/xfs/2013-03/msg00144.html for more details about the reproduction case and why this solution was chosen. Based on idea by Dave Chinner . CC: Dave Chinner Signed-off-by: Jan Kara Reviewed-by: Dave Chinner Reviewed-by: Mark Tinguely Signed-off-by: Ben Myers :040000 040000 e985da5ddb4802b70b70f5729bf8f2955dc75a1f 9adc5822188e0e0042dffaffc52196dd22440325 M fs bisect run success ls -a /kernel-tests/run-queue/kvm/x86_64-nfsroot/xfs:for-next:f722406faae2d073cc1d01063d1123c35425939e:bisect-mm 2013-06-15-06:47:19 f722406faae2d073cc1d01063d1123c35425939e reuse /kernel/x86_64-nfsroot/f722406faae2d073cc1d01063d1123c35425939e/vmlinuz-3.10.0-rc1 2013-06-15-06:47:19 detecting boot state .. 6 21 25 37 40 51 60 61 63 73 86. 87 89 103 107.. 116 123 129. 132 136 140 142.. 145 153. 155 172 182 184 185 188 192 194. 195. 202. 206 207 214 215 217. 230 231. 235 239 241.. 249 254 256 257 261 272 282 287. 294 298.. 299....................................................................................................................................................................................................................................................................................................... 300 SUCCESS ls -a /kernel-tests/run-queue/kvm/x86_64-nfsroot/xfs:for-next:ade1335afef556df6538eb02e8c0dc91fbd9cc37:bisect-mm TEST FAILURE /kernel/x86_64-nfsroot/ade1335afef556df6538eb02e8c0dc91fbd9cc37/dmesg-kvm-kbuild-31646-20130615005640-3.10.0-rc1-00031-gade1335-1508 /kernel/x86_64-nfsroot/ade1335afef556df6538eb02e8c0dc91fbd9cc37/dmesg-kvm-stoakley-4353-20130615063155-3.10.0-rc1-00031-gade1335-1508 /kernel/x86_64-nfsroot/ade1335afef556df6538eb02e8c0dc91fbd9cc37/dmesg-kvm-vp-14105-20130615090604-3.10.0-rc1-00031-gade1335-1508 /kernel/x86_64-nfsroot/ade1335afef556df6538eb02e8c0dc91fbd9cc37/dmesg-kvm-xgwo-25228-20130615090438-3.10.0-rc1-00031-gade1335-1508 [detached HEAD 7872bbb] Revert "xfs: Avoid pathological backwards allocation" 1 file changed, 6 insertions(+), 18 deletions(-) ls -a /kernel-tests/run-queue/kvm/x86_64-nfsroot/xfs:for-next:7872bbb055d8070cdd8e7691d7a4181fbfa43caa:bisect-mm 2013-06-15-09:52:35 7872bbb055d8070cdd8e7691d7a4181fbfa43caa compiling 2013-06-15-09:55:30 detecting boot state 3.10.0-rc1-00032-g7872bbb...... 2 TEST FAILURE dmesg-kvm-vp-15998-20130615100040-3.10.0-rc1-00032-g7872bbb-23 dmesg-kvm-vp-13785-20130615100046-3.10.0-rc1-00032-g7872bbb-23 dmesg-kvm-vp-37754-20130615100046-3.10.0-rc1-00032-g7872bbb-23 dmesg-kvm-vp-28199-20130615100047-3.10.0-rc1-00032-g7872bbb-23 ========= upstream ========= Fetching linus ls -a /kernel-tests/run-queue/kvm/x86_64-nfsroot/xfs:for-next:a2648ebb7ed69ef209d9c8a76fadeb3252d9a023:bisect-mm 2013-06-15-09:59:03 a2648ebb7ed69ef209d9c8a76fadeb3252d9a023 reuse /kernel/x86_64-nfsroot/a2648ebb7ed69ef209d9c8a76fadeb3252d9a023/vmlinuz-3.10.0-rc5-00204-ga2648eb 2013-06-15-09:59:03 detecting boot state ........ TEST FAILURE dmesg-kvm-stoakley-4683-20130615100228-3.10.0-rc5-00204-ga2648eb-1496 dmesg-kvm-stoakley-3899-20130615100255-3.10.0-rc5-00204-ga2648eb-1496 dmesg-kvm-stoakley-4592-20130615100255-3.10.0-rc5-00204-ga2648eb-1496 ========= linux-next ========= Fetching next ls -a /kernel-tests/run-queue/kvm/x86_64-nfsroot/xfs:for-next:c04efed734409f5a44715b54a6ca1b54b0ccf215:bisect-mm 2013-06-15-10:03:07 c04efed734409f5a44715b54a6ca1b54b0ccf215 reuse /kernel/x86_64-nfsroot/c04efed734409f5a44715b54a6ca1b54b0ccf215/vmlinuz-3.10.0-rc4-next-20130607 2013-06-15-10:03:07 detecting boot state ...... TEST FAILURE dmesg-kvm-stoakley-3811-20130615100534-3.10.0-rc4-next-20130607-1297