2024/08/19-23:49:06.643970 140500439492160 DEBG dcompact_worker.cpp:2211: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-00341/att-00: fork to child time = 0.026829 sec 2024/08/19-23:49:06.645141 140500439492160 DEBG dcompact_worker.cpp:1011: Beg SerDeRead: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-00341/att-00 2024/08/19-23:49:06.651155 140500439492160 DEBG dcompact_worker.cpp:1031: End SerDeRead: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-00341/att-00 2024/08/19-23:49:06.652942 140500439492160 TRAC dcompact_worker.cpp:1081: INFO_LOG_LEVEL: rpc = INFO_LEVEL, env_var = undefined 2024/08/19-23:49:06.653376 140500439492160 [WARN] [column_family.cc:386] multiple cf_paths/db_paths and level_compaction_dynamic_level_bytes can't be used together 2024/08/19-23:49:06.689295 140500439492160 [version_set.cc:6139] Recovering from manifest file: /worker/dcompact-log/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/2024-08-19T23.41.30/.rocksdb/job-00341/att-00/MANIFEST-14619535 2024/08/19-23:49:06.741051 140500439492160 [version_set.cc:6182] Recovered from manifest file:/worker/dcompact-log/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/2024-08-19T23.41.30/.rocksdb/job-00341/att-00/MANIFEST-14619535 succeeded,manifest_file_number is 14619535, next_file_number is 14619887, last_sequence is 189584142595, log_number is 0,prev_log_number is 0,max_column_family is 0,min_log_number_to_keep is 14619686 2024/08/19-23:49:06.741068 140500439492160 [version_set.cc:6197] Column family [default] (ID 0), log number is 0 2024/08/19-23:49:06.741174 140500439492160 [version_set.cc:5652] Creating manifest 14619887 2024/08/19-23:49:06.765177 140500439492160 DEBG dcompact_worker.cpp:1215: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-00341/att-00: bottommost_level: fake = 1, rpc = 0 2024/08/19-23:49:06.777870 140500439492160 [compaction_job.cc:2433] [default] [JOB 341] Compacting 2@2 + 1@3 files to L3, score 1.08, subcompactions 1 : 1 2024/08/19-23:49:06.777893 140500439492160 [compaction_job.cc:2441] [default]: Compaction start summary: Base version 171 Base level 2, inputs: [14619884(20MB) 14619885(7772KB)], [14619551(38MB)] 2024/08/19-23:49:06.799148 140500439492160 [top_zip_table.cc:59] core git_version_hash_info_is:commit 7517bad5c1a147474c3830831b9a22c996321ae8 Author: leipeng Date: 2024-01-08 19:18:17 +0800 vfork_cmd: call close before wait_finish g++ (GCC) 12.1.0 Copyright (C) 2022 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. INCS = -Isrc -I3rdparty/re2 -I3rdparty/zstd -Iboost-include CXXFLAGS = -D TOPLING_IO_WITH_URING=1 -fPIC -time -Wno-class-memaccess -fdiagnostics-color -Wformat=2 -Wcomment -Wall -Wextra -Wno-unused-parameter -Wno-alloc-size-larger-than -mcx16 -Wno-deprecated-declarations -Wstrict-aliasing=3 -DCLIENT_LICENSE_ID="public" -DNO_THREADS -ftls-model=initial-exec -DDIVSUFSORT_API= -fno-stack-protector RLS_FLAGS = -O3 -DNDEBUG -g3 WITH_BMI2 = 1 compile_cpu_flag: -march=haswell -mbmi -mbmi2 2024/08/19-23:49:06.799218 140500439492160 [top_zip_table.cc:60] fsa git_version_hash_info_is:commit 7517bad5c1a147474c3830831b9a22c996321ae8 Author: leipeng Date: 2024-01-08 19:18:17 +0800 vfork_cmd: call close before wait_finish g++ (GCC) 12.1.0 Copyright (C) 2022 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. INCS = -Isrc -I3rdparty/re2 -I3rdparty/zstd -Iboost-include CXXFLAGS = -D TOPLING_IO_WITH_URING=1 -fPIC -time -Wno-class-memaccess -fdiagnostics-color -Wformat=2 -Wcomment -Wall -Wextra -Wno-unused-parameter -Wno-alloc-size-larger-than -mcx16 -Wno-deprecated-declarations -Wstrict-aliasing=3 -DCLIENT_LICENSE_ID="public" -DNO_THREADS -ftls-model=initial-exec -DDIVSUFSORT_API= -fno-stack-protector RLS_FLAGS = -O3 -DNDEBUG -g3 WITH_BMI2 = 1 compile_cpu_flag: -march=haswell -mbmi -mbmi2 2024/08/19-23:49:06.799255 140500439492160 [top_zip_table.cc:61] zbs git_version_hash_info_is:commit 7517bad5c1a147474c3830831b9a22c996321ae8 Author: leipeng Date: 2024-01-08 19:18:17 +0800 vfork_cmd: call close before wait_finish g++ (GCC) 12.1.0 Copyright (C) 2022 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. INCS = -Isrc -I3rdparty/re2 -I3rdparty/zstd -Iboost-include CXXFLAGS = -D TOPLING_IO_WITH_URING=1 -fPIC -time -Wno-class-memaccess -fdiagnostics-color -Wformat=2 -Wcomment -Wall -Wextra -Wno-unused-parameter -Wno-alloc-size-larger-than -mcx16 -Wno-deprecated-declarations -Wstrict-aliasing=3 -DCLIENT_LICENSE_ID="public" -DNO_THREADS -ftls-model=initial-exec -DDIVSUFSORT_API= -fno-stack-protector RLS_FLAGS = -O3 -DNDEBUG -g3 WITH_BMI2 = 1 compile_cpu_flag: -march=haswell -mbmi -mbmi2 2024/08/19-23:49:06.799270 140500439492160 [top_zip_table.cc:62] topling-zip_table_reader: git_version_hash_info_is: commit 7f80399bfbd2071b6e0f5683e8ab7225b8e6e394 Author: leipeng Date: 2024-01-19 14:52:30 +0800 Change ToplingZipTableOptions::sampleRatio to vector g++ (GCC) 12.1.0 Copyright (C) 2022 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. cpu_flag: -march=native -mbmi -mbmi2 2024/08/19-23:49:06.799284 140500439492160 [top_zip_table.cc:64] topling-rocks git_version_hash_info_is: commit 1240987ca13d0fe562c9b9c037155079f0877840 Author: leipeng Date: 2024-01-19 15:07:04 +0800 Change ToplingZipTableOptions::sampleRatio to vector g++ (GCC) 12.1.0 Copyright (C) 2022 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. cpu_flag: -march=native -mbmi -mbmi2 2024/08/19-23:49:07.252118 140500439492160 [top_zip_table_builder.cc:934] ToplingZipTableBuilder(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-00341/att-00/14619888.sst) /dev/shm/ToplingTemp/Topling-62648-JbfdSj 2024/08/19-23:49:08.911481 140500439492160 [top_zip_table_builder.cc:1344] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-00341/att-00/14619888.sst): first pass time = 1.66's, 80.888'MB/sec 2024/08/19-23:49:13.351477 140500439492160 [top_zip_table_builder.cc:2764] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-00341/att-00/14619888.sst): old prealloc_size = 77809210, real_size = 36035296 2024/08/19-23:49:13.352137 140500439492160 [top_zip_table_builder.cc:1765] BuildReorderMap(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-00341/att-00/14619888.sst): index type = NestLoudsTrieDAWG_Mixed_XL_256_32_FL, store type = DictZipBlobStore usrkeys = 933922 prefix = 4 raw-key = 0.0149 GB zip-key = 0.0018 GB avg-key = 16.00 avg-zkey = 1.90 raw-val = 0.1081 GB zip-val = 0.0340 GB avg-val = 115.71 avg-zval = 36.43 2024/08/19-23:49:13.352957 140500439492160 [top_zip_table_builder.cc:1295] /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-00341/att-00/14619888.sst: sumWaitingMem = 0.002 GB, sumWorkingMem = 0.020 GB, reorder workingMem = 0.0023 GB, waited 0.000 sec, Key+Value = 0.134 GB 2024/08/19-23:49:14.134916 140500439492160 [top_zip_table_builder.cc:3092] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-00341/att-00/14619888.sst): second pass time = 4.44's, 24.344'MB/sec, value only(80.5% of KV) wait indexing time = 0.00's, remap KeyValue time = 0.78's, 51.106'MB/sec (all stages of remap) Get OrderMap time = 0.00's, 2853.605'MB/sec (index lex order gen) rebuild zvType time = 0.63's, 0.369'MB/sec write SST data time = 0.15's, 267.925'MB/sec dict compress time = 4356233619.02's, 0.000'MB/sec z-dict build time = 0.00's, sample length = 1.078'MB, throughput = 23107.758'MB/sec zip my value time = 4.44's, unzip length = 0.108'GB zip my value throughput = 24.344'MB/sec zip pipeline throughput = 130.776'MB/sec entries = 933922 avg-key = 28.00 avg-zkey = 1.90 avg-val = 115.71 avg-zval = 36.43 usrkeys = 933922 avg-key = 20.00 avg-zkey = 1.90 avg-val = 122.71 avg-zval = 36.43 TagRS{ kinds = RS_Key0_Tag1 bytes = 0 } TagArray{ size = 933922 bytes = 3152000 } seq expand size = 6537454 multi value expand size = 0 cnt WriteAppend = 12 UnZipSize{ index = 0.0187 GB value = 0.1081 GB dict = 1.08 MB all = 0.1342 GB } __ZipSize{ index = 0.0018 GB value = 0.0340 GB dict = 1.08 MB all = 0.0400 GB } UnZip/Zip{ index = 10.5141 value = 3.1761 dict = 1.00 all = 3.3523 } Zip/UnZip{ index = 0.0951 value = 0.3148 dict = 1.00 all = 0.2983 } ---------------------------- total value len = 62.411355 GB avg = 0.180 KB (by entry num) total key len = 6.814907 GB avg = 0.020 KB total ukey len = 3.208186 GB avg = 0.008 KB total ukey num = 0.390267483 Billion total entry num = 0.347145491 Billion write speed all = 3.074955380 MB/sec (with seq num) write speed all = 2.951596776 MB/sec (without seq num) 2024/08/19-23:49:14.186472 140500439492160 [compaction_job.cc:1944] [default] [JOB 341] Generated table #14619888: 933922 keys, 40037905 bytes, temperature: kWarm 2024/08/19-23:49:14.186593 140500439492160 EVENT_LOG_v1 {"time_micros": 1724082554186524, "cf_name": "default", "job": 341, "event": "table_file_creation", "file_number": 14619888, "file_size": 40037905, "file_checksum": "", "file_checksum_func_name": "Unknown", "smallest_seqno": 189479469885, "largest_seqno": 189575469348, "table_properties": {"data_size": 34025104, "index_size": 1776512, "index_partitions": 0, "top_level_index_size": 0, "index_key_is_user_key": 0, "index_value_is_delta_encoded": 0, "filter_size": 0, "raw_key_size": 26149816, "raw_average_key_size": 28, "raw_value_size": 108068008, "raw_average_value_size": 115, "num_data_blocks": 1, "num_entries": 933922, "num_filter_entries": 0, "num_deletions": 0, "num_merge_operands": 0, "num_range_deletions": 0, "format_version": 0, "fixed_key_len": 28, "fixed_value_len": 18446744073709551615, "filter_policy": "", "column_family_name": "default", "column_family_id": 0, "comparator": "leveldb.BytewiseComparator", "merge_operator": "nullptr", "prefix_extractor_name": "nullptr", "property_collectors": "[Rdb_tbl_prop_coll_factory]", "compression": "FlatZip", "compression_options": "RS_Key0_Tag1-NestLoudsTrieDAWG_Mixed_XL_256_32_FL-DictZipBlobStore", "creation_time": 1724082547, "oldest_key_time": 0, "file_creation_time": 1724082547, "slow_compression_estimated_data_size": 0, "fast_compression_estimated_data_size": 0, "db_id": "a007a635-5c0a-4b4a-be96-b9c695cb016b", "db_session_id": "9474K4QZ2QA6TIYF9LEW", "orig_file_number": 14619888, "seqno_to_time_mapping": "N/A", "__indexstats__": "[...1 records...]"}} 2024/08/19-23:49:14.256307 140500439492160 [top_zip_table_builder.cc:934] ToplingZipTableBuilder(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-00341/att-00/14619889.sst) /dev/shm/ToplingTemp/Topling-62648-zaCTwj 2024/08/19-23:49:15.144932 140500439492160 [top_zip_table_builder.cc:1344] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-00341/att-00/14619889.sst): first pass time = 0.89's, 101.895'MB/sec 2024/08/19-23:49:16.360246 140500439492160 [top_zip_table_builder.cc:2764] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-00341/att-00/14619889.sst): old prealloc_size = 77809210, real_size = 27273216 2024/08/19-23:49:16.360712 140500439492160 [top_zip_table_builder.cc:1765] BuildReorderMap(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-00341/att-00/14619889.sst): index type = NestLoudsTrieDAWG_Mixed_XL_256_32_FL, store type = DictZipBlobStore usrkeys = 627748 prefix = 4 raw-key = 0.0100 GB zip-key = 0.0012 GB avg-key = 16.00 avg-zkey = 1.90 raw-val = 0.0729 GB zip-val = 0.0259 GB avg-val = 116.09 avg-zval = 41.29 2024/08/19-23:49:16.361280 140500439492160 [top_zip_table_builder.cc:1295] /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-00341/att-00/14619889.sst: sumWaitingMem = 0.002 GB, sumWorkingMem = 0.020 GB, reorder workingMem = 0.0016 GB, waited 0.000 sec, Key+Value = 0.090 GB 2024/08/19-23:49:17.220777 140500439492160 [top_zip_table_builder.cc:3092] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-00341/att-00/14619889.sst): second pass time = 1.20's, 60.640'MB/sec, value only(80.6% of KV) wait indexing time = 0.01's, remap KeyValue time = 0.86's, 34.740'MB/sec (all stages of remap) Get OrderMap time = 0.00's, 2761.430'MB/sec (index lex order gen) rebuild zvType time = 0.67's, 0.235'MB/sec write SST data time = 0.19's, 154.988'MB/sec dict compress time = 4356233619.02's, 0.000'MB/sec z-dict build time = 0.00's, sample length = 0.731'MB, throughput = 19707.437'MB/sec zip my value time = 1.20's, unzip length = 0.073'GB zip my value throughput = 60.640'MB/sec zip pipeline throughput = 60.640'MB/sec entries = 627748 avg-key = 28.00 avg-zkey = 1.90 avg-val = 116.09 avg-zval = 41.29 usrkeys = 627748 avg-key = 20.00 avg-zkey = 1.90 avg-val = 123.09 avg-zval = 41.29 TagRS{ kinds = RS_Key0_Tag1 bytes = 0 } TagArray{ size = 627748 bytes = 2040192 } seq expand size = 4394236 multi value expand size = 0 cnt WriteAppend = 12 UnZipSize{ index = 0.0126 GB value = 0.0729 GB dict = 0.73 MB all = 0.0905 GB } __ZipSize{ index = 0.0012 GB value = 0.0259 GB dict = 0.73 MB all = 0.0299 GB } UnZip/Zip{ index = 10.5050 value = 2.8115 dict = 1.00 all = 3.0258 } Zip/UnZip{ index = 0.0952 value = 0.3557 dict = 1.00 all = 0.3305 } ---------------------------- total value len = 62.488626 GB avg = 0.180 KB (by entry num) total key len = 6.832484 GB avg = 0.020 KB total ukey len = 3.220741 GB avg = 0.008 KB total ukey num = 0.390895231 Billion total entry num = 0.347773239 Billion write speed all = 3.078746386 MB/sec (with seq num) write speed all = 2.955181647 MB/sec (without seq num) 2024/08/19-23:49:17.259868 140500439492160 [compaction_job.cc:1944] [default] [JOB 341] Generated table #14619889: 627748 keys, 29894214 bytes, temperature: kWarm 2024/08/19-23:49:17.260000 140500439492160 EVENT_LOG_v1 {"time_micros": 1724082557259909, "cf_name": "default", "job": 341, "event": "table_file_creation", "file_number": 14619889, "file_size": 29894214, "file_checksum": "", "file_checksum_func_name": "Unknown", "smallest_seqno": 189542769945, "largest_seqno": 189583805442, "table_properties": {"data_size": 25920944, "index_size": 1195136, "index_partitions": 0, "top_level_index_size": 0, "index_key_is_user_key": 0, "index_value_is_delta_encoded": 0, "filter_size": 0, "raw_key_size": 17576944, "raw_average_key_size": 28, "raw_value_size": 72876044, "raw_average_value_size": 116, "num_data_blocks": 1, "num_entries": 627748, "num_filter_entries": 0, "num_deletions": 0, "num_merge_operands": 0, "num_range_deletions": 0, "format_version": 0, "fixed_key_len": 28, "fixed_value_len": 18446744073709551615, "filter_policy": "", "column_family_name": "default", "column_family_id": 0, "comparator": "leveldb.BytewiseComparator", "merge_operator": "nullptr", "prefix_extractor_name": "nullptr", "property_collectors": "[Rdb_tbl_prop_coll_factory]", "compression": "FlatZip", "compression_options": "RS_Key0_Tag1-NestLoudsTrieDAWG_Mixed_XL_256_32_FL-DictZipBlobStore", "creation_time": 1724082554, "oldest_key_time": 0, "file_creation_time": 1724082554, "slow_compression_estimated_data_size": 0, "fast_compression_estimated_data_size": 0, "db_id": "a007a635-5c0a-4b4a-be96-b9c695cb016b", "db_session_id": "9474K4QZ2QA6TIYF9LEW", "orig_file_number": 14619889, "seqno_to_time_mapping": "N/A", "__indexstats__": "[...1 records...]"}} 2024/08/19-23:49:17.296339 140500439492160 [compaction_job.cc:699] job-00341: subcompact[0], size: 0.069932 G, files: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-00341/att-00 [14619888,14619889] 2024/08/19-23:49:17.336022 140500439492160 (Original Log Time 2024/08/19-23:49:06.778019) EVENT_LOG_v1 {"time_micros": 1724082546777916, "job": 341, "event": "compaction_started", "compaction_reason": "LevelMaxLevelSize", "files_L2": [14619884, 14619885], "files_L3": [14619551], "score": 1.07812, "input_data_size": 70735646, "oldest_snapshot_seqno": 189584140750} 2024/08/19-23:49:17.336028 140500439492160 (Original Log Time 2024/08/19-23:49:17.332548) [compaction_job.cc:2018] [default] [JOB 341] Compacted 2@2 + 1@3 files to L3 => 69932119 bytes 2024/08/19-23:49:17.336031 140500439492160 (Original Log Time 2024/08/19-23:49:17.335917) [compaction_job.cc:1220] [default] compacted to: files[0 0 0 2 0 0 0] max score 0.00, MB/sec: 6.7 rd, 6.6 wr, level 3, files in(2, 1) out(2 +0 blob) MB in(28.5, 39.0 +0.0 blob) out(66.7 +0.0 blob), read-write-amplify(4.7) write-amplify(2.3) OK, records in: 1561670, records dropped: 0 output_compression: Snappy 2024/08/19-23:49:17.336042 140500439492160 (Original Log Time 2024/08/19-23:49:17.335993) EVENT_LOG_v1 {"time_micros": 1724082557335962, "cf": "default", "job": 341, "event": "compaction_finished", "compaction_time_micros": 10518335, "compaction_time_cpu_micros": 3284412, "output_level": 3, "num_output_files": 2, "total_output_size": 69932119, "num_input_records": 1561670, "num_output_records": 1561670, "num_subcompactions": 1, "output_compression": "Snappy", "num_single_delete_mismatches": 0, "num_single_delete_fallthrough": 0, "file_write_nanos": 54577847, "file_range_sync_nanos": 0, "file_fsync_nanos": 1511, "file_prepare_write_nanos": 5824, "lsm_state": [0, 0, 0, 2, 0, 0, 0]} 2024/08/19-23:49:17.485812 140500439492160 DEBG dcompact_worker.cpp:240: HttpPost: 200 OK: url = http://nlb-7zny4kaa1poal01o64.cn-shenzhen.nlb.aliyuncs.com:8443, body = {"instanceId":"nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137","labourId":"","dbId":"a007a635-5c0a-4b4a-be96-b9c695cb016b","dbStarts":1724082090,"starts":1724082546,"executesMs":10681,"compactionJobId":341,"attempt":0,"compactionInputRawBytes":224670812,"compactionInputZipBytes":70735646,"compactionOutputRawBytes":0,"compactionOutputZipBytes":69932119,"headers":{"Accept":"*/*","Connection":"close","Host":"aliyun-topling-saas.topling.cn:18443","RemoteIp":"120.24.192.169","X-Forwarded-For":"120.24.192.169","region":"cn-shenzhen","token":"e6474c481bd4415abc537135cc03626b","instance-token":"e6474c481bd4415abc537135cc03626b","provider":"aliyun","CloudMarketInstanceId":"si-59c0ae5c955845588903","MeteringAssit":"","Transfer-Encoding":"chunked","traceparent":"00-198a05797a6cd9a534dff9cdfd07f058-c9de3f6226ae04bc-00"}}, response = 2024/08/19-23:49:17.485957 140500439492160 INFO dcompact_worker.cpp:1456: finish /worker/dcompact-log/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/2024-08-19T23.41.30/.rocksdb/job-00341/att-00: olev 3, work 10.682 s, result 6.332 ms, install 3.528 ms, input{raw 214.263 MiB zip 67.459 MiB}