Currently it has been popular that single disk could be more than TiB, etc 16Tib with only one single disk, with this trend, one single filesystem could be larger and larger and easily reach PiB with LUN system. The journal filesystem like ext4 need be offline to do regular check and repair from time to time, however the problem is e2fsck still do this using single thread, this could be challenging at scale for two reasons: 1) even with readahead, IO speed still limits several tens MiB per second. 2) could not utilize CPU cores. It could be challenging to try multh-threads for all phase of e2fsck, but as first step, we might try this for most time-consuming pass1, according to our benchmarking it cost of 80% time for whole e2fck phase. Pass1 is trying to scanning all valid inode of filesystem and check it one by one, and the patchset idea is trying to split these to different threads and trying to do this at the same time, we try to merge these inodes and corresponding inode's extent information after threads finish. To simplify complexity and make it less error-prone, the fix is still serialized, since most of time there will be only minor errors for filesystem, what's important for us is parallel reading and checking. Here is a benchmarking on our Lustre filesystem with 1.2 PiB OSD ext4 based filesystem: DDN SFA18KE StorageServer DCR(DeClustering RAID) with 162 x HGST 10TB NL-SAS Tested Server A Virtual Machine running on SFA18KE 8 x CPU cores (Xeon(R) Gold 6140) 150GB memory CentoOS7.7 (Lustre patched kernel) Created 600 Million x 32K byte files. Without Patch With Patch thr=64 pass1: 13079.66 488.57 seconds Total: 15673.33 3188.42 We have 5x total time reduction of total time which is very inspiring. I've tested the whole patch series using 'make test' of e2fsck itself, and i manually set default threads to 4 which still pass almost of test suite, failure cases are below: f_h_badroot f_multithread f_multithread_logfile f_multithread_no f_multithread_ok h_h_badroot failed because out of order checking output, and others are because of extra multiple threads log output. The other test i've done to verify is: 1) filled a filesystem with different features enabled(encryption, shared xattr) 2) copied the above image out using e2image. 3) using e2fuzz to randomly corrupt above image, and then have another copy of corrupted image. 4) running e2fsck with single thread(without patches) and multiple threads with corrupted image respectively. 5) using valgrind to check any memory leak. 6) compare single thread and multiple threads fix results by mounting two images back and compare the directores and files.(size and name match) Any review or comments are welcomed! Thanks you very much! changelog v2->v3: 1) Parallelize rw_bitmaps 2) Configuration to turn off parallel fsck.(default=on) 3) Add f_multithread_ok 4) Add annotations to e2fsck_struct instead of reshuffle 5) Fix memory leaks 6) Some more extra fixes Andreas Dilger (2): e2fsck: fix f_multithread_ok test e2fsck: misc cleanups for pfsck Li Xi (18): e2fsck: add -m option for multithread e2fsck: copy context when using multi-thread fsck e2fsck: copy fs when using multi-thread fsck e2fsck: add assert when copying context e2fsck: copy bitmaps when copying context e2fsck: open io-channel when copying fs e2fsck: create logs for mult-threads e2fsck: optionally configure one pfsck thread e2fsck: add start/end group for thread e2fsck: split groups to different threads e2fsck: print thread log properly e2fsck: do not change global variables e2fsck: optimize the inserting of dir_info_db e2fsck: merge dir_info after thread finishes e2fsck: merge icounts after thread finishes e2fsck: merge dblist after thread finishes e2fsck: add debug codes for multiple threads e2fsck: merge fs flags when threads finish Saranya Muruganandam (2): e2fsck: propagate number of threads e2fsck: Annotating fields in e2fsck_struct Wang Shilong (39): e2fsck: clear icache when using multi-thread fsck e2fsck: copy badblocks when copying fs e2fsck: merge bitmaps after thread completes e2fsck: rbtree bitmap for dir e2fsck: merge badblocks after thread finishes e2fsck: merge counts after threads finish e2fsck: merge dx_dir_info after threads finish e2fsck: merge dirs_to_hash when threads finish e2fsck: merge context flags properly e2fsck: merge quota context after threads finish e2fsck: serialize fix operations e2fsck: move some fixes out of parallel pthreads e2fsck: split and merge invalid bitmaps e2fsck: merge EA blocks properly e2fsck: kickoff mutex lock for block found map e2fsck: allow admin specify number of threads e2fsck: adjust number of threads e2fsck: fix readahead for pfsck of pass1 e2fsck: merge options after threads finish e2fsck: reset lost_and_found after threads finish e2fsck: merge extent depth count after threads finish e2fsck: simplify e2fsck context merging codes e2fsck: set E2F_FLAG_ALLOC_OK after threads e2fsck: wait fix thread finish before checking e2fsck: cleanup e2fsck_pass1_thread_join() e2fsck: avoid too much memory allocation for pfsck e2fsck: make default smallest RA size to 1M ext2fs: parallel bitmap loading e2fsck: update mmp block in one thread e2fsck: reset @inodes_to_rebuild if restart e2fsck: fix build for make rpm e2fsck: move ext2fs_get_avg_group to rw_bitmaps.c configure: enable pfsck by default test: add pfsck test e2fsck: fix race in ext2fs_read_bitmaps() e2fsck: fix readahead for pass1 without pfsck e2fsck: fix memory leaks with pfsck enabled ext2fs: fix to set tail flags with pfsck enabled e2fsck: update mmp block race MCONFIG.in | 1 + configure | 90 +- configure.ac | 26 + e2fsck/Makefile.in | 9 +- e2fsck/dirinfo.c | 238 ++- e2fsck/dx_dirinfo.c | 64 + e2fsck/e2fsck.8.in | 8 +- e2fsck/e2fsck.c | 11 + e2fsck/e2fsck.h | 102 +- e2fsck/logfile.c | 13 +- e2fsck/pass1.c | 1766 ++++++++++++++++++++--- e2fsck/problem.c | 11 + e2fsck/problem.h | 3 + e2fsck/readahead.c | 4 + e2fsck/unix.c | 59 +- e2fsck/util.c | 193 ++- lib/config.h.in | 3 + lib/ext2fs/badblocks.c | 85 +- lib/ext2fs/bitmaps.c | 10 + lib/ext2fs/bitops.h | 2 + lib/ext2fs/blkmap64_rb.c | 65 + lib/ext2fs/bmap64.h | 4 + lib/ext2fs/dblist.c | 38 + lib/ext2fs/ext2_err.et.in | 3 + lib/ext2fs/ext2_io.h | 2 + lib/ext2fs/ext2fs.h | 19 +- lib/ext2fs/ext2fsP.h | 1 - lib/ext2fs/gen_bitmap64.c | 62 + lib/ext2fs/icount.c | 107 ++ lib/ext2fs/openfs.c | 48 +- lib/ext2fs/rw_bitmaps.c | 301 +++- lib/ext2fs/undo_io.c | 19 + lib/ext2fs/unix_io.c | 24 +- lib/support/mkquota.c | 39 + lib/support/quotaio.h | 3 + tests/f_itable_collision/expect.1 | 3 - tests/f_multithread/expect.1 | 25 + tests/f_multithread/expect.2 | 7 + tests/f_multithread/image.gz | 1 + tests/f_multithread/name | 1 + tests/f_multithread/script | 4 + tests/f_multithread_completion/expect.1 | 2 + tests/f_multithread_completion/expect.2 | 23 + tests/f_multithread_completion/image.gz | 1 + tests/f_multithread_completion/name | 1 + tests/f_multithread_completion/script | 4 + tests/f_multithread_logfile/expect.1 | 25 + tests/f_multithread_logfile/image.gz | 1 + tests/f_multithread_logfile/name | 1 + tests/f_multithread_logfile/script | 32 + tests/f_multithread_no/expect.1 | 26 + tests/f_multithread_no/expect.2 | 23 + tests/f_multithread_no/image.gz | 1 + tests/f_multithread_no/name | 1 + tests/f_multithread_no/script | 4 + tests/f_multithread_ok/expect.1 | 8 + tests/f_multithread_ok/image.gz | Bin 0 -> 796311 bytes tests/f_multithread_ok/name | 1 + tests/f_multithread_ok/script | 21 + tests/f_multithread_preen/expect.1 | 11 + tests/f_multithread_preen/expect.2 | 23 + tests/f_multithread_preen/image.gz | 1 + tests/f_multithread_preen/name | 1 + tests/f_multithread_preen/script | 4 + tests/f_multithread_yes/expect.1 | 2 + tests/f_multithread_yes/expect.2 | 23 + tests/f_multithread_yes/image.gz | 1 + tests/f_multithread_yes/name | 1 + tests/f_multithread_yes/script | 4 + tests/test_one.in | 8 + 70 files changed, 3335 insertions(+), 393 deletions(-) create mode 100644 tests/f_multithread/expect.1 create mode 100644 tests/f_multithread/expect.2 create mode 120000 tests/f_multithread/image.gz create mode 100644 tests/f_multithread/name create mode 100644 tests/f_multithread/script create mode 100644 tests/f_multithread_completion/expect.1 create mode 100644 tests/f_multithread_completion/expect.2 create mode 120000 tests/f_multithread_completion/image.gz create mode 100644 tests/f_multithread_completion/name create mode 100644 tests/f_multithread_completion/script create mode 100644 tests/f_multithread_logfile/expect.1 create mode 120000 tests/f_multithread_logfile/image.gz create mode 100644 tests/f_multithread_logfile/name create mode 100644 tests/f_multithread_logfile/script create mode 100644 tests/f_multithread_no/expect.1 create mode 100644 tests/f_multithread_no/expect.2 create mode 120000 tests/f_multithread_no/image.gz create mode 100644 tests/f_multithread_no/name create mode 100644 tests/f_multithread_no/script create mode 100644 tests/f_multithread_ok/expect.1 create mode 100644 tests/f_multithread_ok/image.gz create mode 100644 tests/f_multithread_ok/name create mode 100644 tests/f_multithread_ok/script create mode 100644 tests/f_multithread_preen/expect.1 create mode 100644 tests/f_multithread_preen/expect.2 create mode 120000 tests/f_multithread_preen/image.gz create mode 100644 tests/f_multithread_preen/name create mode 100644 tests/f_multithread_preen/script create mode 100644 tests/f_multithread_yes/expect.1 create mode 100644 tests/f_multithread_yes/expect.2 create mode 120000 tests/f_multithread_yes/image.gz create mode 100644 tests/f_multithread_yes/name create mode 100644 tests/f_multithread_yes/script -- 2.29.2.299.gdc1121823c-goog
