Zoltan Martonka has posted comments on this change. ( http://gerrit.cloudera.org:8080/20680 )
Change subject: KUDU-3523 Use f_bsize as Kudu block size instead of st_blksize ...................................................................... Patch Set 4: I looked into LogBlockManagerTest/ContainerPreallocationTest on our cloudera rhel (Xixu probably has a similar setup). 64k kernel with 4k disk. The following happens: + The encryption header is written without preallocating FLAGS_log_container_preallocate_bytes bytes. + When we try to write some data, kudu round up the current byte size to 64k and tries to allocate the next block from there until FLAGS_log_container_preallocate_bytes bytes. But it should round to 4k, because f_bsize is 4k and it is the one that allocate/hole punch uses. Since FLAGS_log_container_preallocate_bytes=33554432, Kudu expects to have 512 64k continuous block reserved. Instead it will have a 4k block, then 15*4k holes, and then 16*512 4k block reserved again. It is clearly kudu wrong and not the system api. If you wish to debug it yourself and make your own conclusion I would suggest: + on log_block_manager-test.cc line remove the false from INSTANTIATE_TEST_SUITE_P(...) + put a breakpoint in log_block_manager.cc line 1635: RETURN_NOT_OK_HANDLE_ERROR(data_file_->PreAllocate(off, len, RWFile::CHANGE_FILE_SIZE)); + Run ContainerPreallocationTest. When it stops in the breakpoint, you can check that the file is only 4k, and it tries to allocate after 64k. -- To view, visit http://gerrit.cloudera.org:8080/20680 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: kudu Gerrit-Branch: master Gerrit-MessageType: comment Gerrit-Change-Id: I04343caf5fe377a4fa9b57e6e450307e6b995928 Gerrit-Change-Number: 20680 Gerrit-PatchSet: 4 Gerrit-Owner: Wang Xixu <1450306...@qq.com> Gerrit-Reviewer: Alexey Serbin <ale...@apache.org> Gerrit-Reviewer: Ashwani Raina <ara...@cloudera.com> Gerrit-Reviewer: Attila Bukor <abu...@apache.org> Gerrit-Reviewer: Kudu Jenkins (120) Gerrit-Reviewer: Wang Xixu <1450306...@qq.com> Gerrit-Reviewer: Yifan Zhang <chinazhangyi...@163.com> Gerrit-Reviewer: Yingchun Lai <laiyingc...@apache.org> Gerrit-Reviewer: Zoltan Martonka <zmarto...@cloudera.com> Gerrit-Comment-Date: Thu, 14 Dec 2023 14:19:59 +0000 Gerrit-HasComments: No
