2024/08/20-04:16:24.549285 140500154140224 DEBG dcompact_worker.cpp:2211: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05951/att-00: fork to child time = 0.010292 sec 2024/08/20-04:16:24.550334 140500154140224 DEBG dcompact_worker.cpp:1011: Beg SerDeRead: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05951/att-00 2024/08/20-04:16:24.555157 140500154140224 DEBG dcompact_worker.cpp:1031: End SerDeRead: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05951/att-00 2024/08/20-04:16:24.558295 140500154140224 TRAC dcompact_worker.cpp:1081: INFO_LOG_LEVEL: rpc = INFO_LEVEL, env_var = undefined 2024/08/20-04:16:24.558574 140500154140224 [WARN] [column_family.cc:386] multiple cf_paths/db_paths and level_compaction_dynamic_level_bytes can't be used together 2024/08/20-04:16:24.669139 140500154140224 [version_set.cc:6139] Recovering from manifest file: /worker/dcompact-log/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/2024-08-20T02.42.00/.rocksdb/job-05951/att-00/MANIFEST-14629260 2024/08/20-04:16:24.717497 140500154140224 [version_set.cc:6182] Recovered from manifest file:/worker/dcompact-log/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/2024-08-20T02.42.00/.rocksdb/job-05951/att-00/MANIFEST-14629260 succeeded,manifest_file_number is 14629260, next_file_number is 14635910, last_sequence is 189931578068, log_number is 0,prev_log_number is 0,max_column_family is 0,min_log_number_to_keep is 14635739 2024/08/20-04:16:24.717506 140500154140224 [version_set.cc:6197] Column family [default] (ID 0), log number is 0 2024/08/20-04:16:24.717571 140500154140224 [version_set.cc:5652] Creating manifest 14635910 2024/08/20-04:16:24.743919 140500154140224 DEBG dcompact_worker.cpp:1215: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05951/att-00: bottommost_level: fake = 1, rpc = 0 2024/08/20-04:16:24.764494 140500154140224 [compaction_job.cc:2433] [default] [JOB 5951] Compacting 1@2 + 1@3 files to L3, score 1.10, subcompactions 1 : 1 2024/08/20-04:16:24.764505 140500154140224 [compaction_job.cc:2441] [default]: Compaction start summary: Base version 3110 Base level 2, inputs: [14635906(20MB)], [14634700(39MB)] 2024/08/20-04:16:24.769895 140500154140224 [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 2024/08/20-04:16:24.769954 140500154140224 [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 2024/08/20-04:16:24.769986 140500154140224 [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 2024/08/20-04:16:24.769998 140500154140224 [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 2024/08/20-04:16:24.770007 140500154140224 [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 2024/08/20-04:16:25.214218 140500154140224 [top_zip_table_builder.cc:934] ToplingZipTableBuilder(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05951/att-00/14635911.sst) /dev/shm/ToplingTemp/Topling-163999-56Vd9Z 2024/08/20-04:16:25.922416 140500154140224 [top_zip_table_builder.cc:1344] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05951/att-00/14635911.sst): first pass time = 0.71's, 189.535'MB/sec 2024/08/20-04:16:28.224803 140500154140224 [top_zip_table_builder.cc:2764] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05951/att-00/14635911.sst): old prealloc_size = 69181520, real_size = 38224624 2024/08/20-04:16:28.225439 140500154140224 [top_zip_table_builder.cc:1765] BuildReorderMap(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05951/att-00/14635911.sst): index type = NestLoudsTrieDAWG_Mixed_XL_256_32_FL, store type = DictZipBlobStore usrkeys = 927835 prefix = 4 raw-key = 0.0148 GB zip-key = 0.0018 GB avg-key = 16.00 avg-zkey = 1.89 raw-val = 0.1082 GB zip-val = 0.0362 GB avg-val = 116.66 avg-zval = 39.06 2024/08/20-04:16:28.226319 140500154140224 [top_zip_table_builder.cc:1295] /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05951/att-00/14635911.sst: sumWaitingMem = 0.002 GB, sumWorkingMem = 0.020 GB, reorder workingMem = 0.0023 GB, waited 0.000 sec, Key+Value = 0.134 GB 2024/08/20-04:16:29.026108 140500154140224 [top_zip_table_builder.cc:3092] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05951/att-00/14635911.sst): second pass time = 2.30's, 47.034'MB/sec, value only(80.6% of KV) wait indexing time = 0.00's, remap KeyValue time = 0.80's, 52.824'MB/sec (all stages of remap) Get OrderMap time = 0.00's, 2882.723'MB/sec (index lex order gen) rebuild zvType time = 0.64's, 0.364'MB/sec write SST data time = 0.16's, 259.827'MB/sec dict compress time = 4356233619.02's, 0.000'MB/sec z-dict build time = 0.00's, sample length = 1.080'MB, throughput = 27418.793'MB/sec zip my value time = 2.30's, unzip length = 0.108'GB zip my value throughput = 47.034'MB/sec zip pipeline throughput = 92.417'MB/sec entries = 927835 avg-key = 28.00 avg-zkey = 1.89 avg-val = 116.66 avg-zval = 39.06 usrkeys = 927835 avg-key = 20.00 avg-zkey = 1.89 avg-val = 123.66 avg-zval = 39.06 TagRS{ kinds = RS_Key0_Tag1 bytes = 0 } TagArray{ size = 927835 bytes = 3247440 } seq expand size = 6494845 multi value expand size = 0 cnt WriteAppend = 12 UnZipSize{ index = 0.0186 GB value = 0.1082 GB dict = 1.08 MB all = 0.1342 GB } __ZipSize{ index = 0.0018 GB value = 0.0362 GB dict = 1.08 MB all = 0.0423 GB } UnZip/Zip{ index = 10.5817 value = 2.9868 dict = 1.00 all = 3.1708 } Zip/UnZip{ index = 0.0945 value = 0.3348 dict = 1.00 all = 0.3154 } ---------------------------- total value len = 62.411483 GB avg = 0.180 KB (by entry num) total key len = 6.814737 GB avg = 0.020 KB total ukey len = 3.208064 GB avg = 0.008 KB total ukey num = 0.390261396 Billion total entry num = 0.347139404 Billion write speed all = 1.795852880 MB/sec (with seq num) write speed all = 1.723809507 MB/sec (without seq num) 2024/08/20-04:16:29.076087 140500154140224 [compaction_job.cc:1944] [default] [JOB 5951] Generated table #14635911: 927835 keys, 42329625 bytes, temperature: kWarm 2024/08/20-04:16:29.076170 140500154140224 EVENT_LOG_v1 {"time_micros": 1724098589076124, "cf_name": "default", "job": 5951, "event": "table_file_creation", "file_number": 14635911, "file_size": 42329625, "file_checksum": "", "file_checksum_func_name": "Unknown", "smallest_seqno": 189706194419, "largest_seqno": 189931164454, "table_properties": {"data_size": 36238816, "index_size": 1753664, "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": 25979380, "raw_average_key_size": 28, "raw_value_size": 108238430, "raw_average_value_size": 116, "num_data_blocks": 1, "num_entries": 927835, "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": 1724098585, "oldest_key_time": 0, "file_creation_time": 1724098585, "slow_compression_estimated_data_size": 0, "fast_compression_estimated_data_size": 0, "db_id": "a007a635-5c0a-4b4a-be96-b9c695cb016b", "db_session_id": "90ZT1ZM5QNL093I8HHQG", "orig_file_number": 14635911, "seqno_to_time_mapping": "N/A", "__indexstats__": "[...1 records...]"}} 2024/08/20-04:16:29.123455 140500154140224 [top_zip_table_builder.cc:934] ToplingZipTableBuilder(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05951/att-00/14635912.sst) /dev/shm/ToplingTemp/Topling-163999-Tdpcs2 2024/08/20-04:16:29.345038 140500154140224 [top_zip_table_builder.cc:1344] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05951/att-00/14635912.sst): first pass time = 0.22's, 241.098'MB/sec 2024/08/20-04:16:29.984170 140500154140224 [top_zip_table_builder.cc:2764] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05951/att-00/14635912.sst): old prealloc_size = 69181520, real_size = 14844720 2024/08/20-04:16:29.984490 140500154140224 [top_zip_table_builder.cc:1765] BuildReorderMap(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05951/att-00/14635912.sst): index type = NestLoudsTrieDAWG_Mixed_XL_256_32_FL, store type = DictZipBlobStore usrkeys = 368945 prefix = 4 raw-key = 0.0059 GB zip-key = 0.0007 GB avg-key = 16.00 avg-zkey = 1.92 raw-val = 0.0431 GB zip-val = 0.0140 GB avg-val = 116.77 avg-zval = 38.07 2024/08/20-04:16:29.984848 140500154140224 [top_zip_table_builder.cc:1295] /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05951/att-00/14635912.sst: sumWaitingMem = 0.001 GB, sumWorkingMem = 0.020 GB, reorder workingMem = 0.0009 GB, waited 0.000 sec, Key+Value = 0.053 GB 2024/08/20-04:16:30.443044 140500154140224 [top_zip_table_builder.cc:3092] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05951/att-00/14635912.sst): second pass time = 0.64's, 67.488'MB/sec, value only(80.7% of KV) wait indexing time = 0.00's, remap KeyValue time = 0.46's, 35.920'MB/sec (all stages of remap) Get OrderMap time = 0.00's, 2423.683'MB/sec (index lex order gen) rebuild zvType time = 0.34's, 0.267'MB/sec write SST data time = 0.11's, 144.944'MB/sec dict compress time = 4356233619.02's, 0.000'MB/sec z-dict build time = 0.00's, sample length = 0.435'MB, throughput = 10445.053'MB/sec zip my value time = 0.64's, unzip length = 0.043'GB zip my value throughput = 67.488'MB/sec zip pipeline throughput = 67.488'MB/sec entries = 368945 avg-key = 28.00 avg-zkey = 1.92 avg-val = 116.77 avg-zval = 38.07 usrkeys = 368945 avg-key = 20.00 avg-zkey = 1.92 avg-val = 123.77 avg-zval = 38.07 TagRS{ kinds = RS_Key0_Tag1 bytes = 0 } TagArray{ size = 368945 bytes = 1291328 } seq expand size = 2582615 multi value expand size = 0 cnt WriteAppend = 13 UnZipSize{ index = 0.0074 GB value = 0.0431 GB dict = 0.44 MB all = 0.0534 GB } __ZipSize{ index = 0.0007 GB value = 0.0140 GB dict = 0.44 MB all = 0.0165 GB } UnZip/Zip{ index = 10.4302 value = 3.0675 dict = 1.00 all = 3.2407 } Zip/UnZip{ index = 0.0959 value = 0.3260 dict = 1.00 all = 0.3086 } ---------------------------- total value len = 62.457148 GB avg = 0.180 KB (by entry num) total key len = 6.825068 GB avg = 0.020 KB total ukey len = 3.215443 GB avg = 0.008 KB total ukey num = 0.390630341 Billion total entry num = 0.347508349 Billion write speed all = 1.797239429 MB/sec (with seq num) write speed all = 1.725122138 MB/sec (without seq num) 2024/08/20-04:16:30.469392 140500154140224 [compaction_job.cc:1944] [default] [JOB 5951] Generated table #14635912: 368945 keys, 16481984 bytes, temperature: kWarm 2024/08/20-04:16:30.469478 140500154140224 EVENT_LOG_v1 {"time_micros": 1724098590469432, "cf_name": "default", "job": 5951, "event": "table_file_creation", "file_number": 14635912, "file_size": 16481984, "file_checksum": "", "file_checksum_func_name": "Unknown", "smallest_seqno": 189636722162, "largest_seqno": 189793094921, "table_properties": {"data_size": 14044832, "index_size": 707456, "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": 10330460, "raw_average_key_size": 28, "raw_value_size": 43081918, "raw_average_value_size": 116, "num_data_blocks": 1, "num_entries": 368945, "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": 1724098589, "oldest_key_time": 0, "file_creation_time": 1724098589, "slow_compression_estimated_data_size": 0, "fast_compression_estimated_data_size": 0, "db_id": "a007a635-5c0a-4b4a-be96-b9c695cb016b", "db_session_id": "90ZT1ZM5QNL093I8HHQG", "orig_file_number": 14635912, "seqno_to_time_mapping": "N/A", "__indexstats__": "[...1 records...]"}} 2024/08/20-04:16:30.488634 140500154140224 [compaction_job.cc:699] job-05951: subcompact[0], size: 0.058812 G, files: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05951/att-00 [14635911,14635912] 2024/08/20-04:16:30.527575 140500154140224 (Original Log Time 2024/08/20-04:16:24.764558) EVENT_LOG_v1 {"time_micros": 1724098584764516, "job": 5951, "event": "compaction_started", "compaction_reason": "LevelMaxLevelSize", "files_L2": [14635906], "files_L3": [14634700], "score": 1.10171, "input_data_size": 62892291, "oldest_snapshot_seqno": 189931577323} 2024/08/20-04:16:30.527580 140500154140224 (Original Log Time 2024/08/20-04:16:30.524275) [compaction_job.cc:2018] [default] [JOB 5951] Compacted 1@2 + 1@3 files to L3 => 58811609 bytes 2024/08/20-04:16:30.527583 140500154140224 (Original Log Time 2024/08/20-04:16:30.527485) [compaction_job.cc:1220] [default] compacted to: files[0 0 0 2 0 0 0] max score 0.00, MB/sec: 11.0 rd, 10.3 wr, level 3, files in(1, 1) out(2 +0 blob) MB in(20.2, 39.8 +0.0 blob) out(56.1 +0.0 blob), read-write-amplify(5.7) write-amplify(2.8) OK, records in: 1393234, records dropped: 96454 output_compression: Snappy 2024/08/20-04:16:30.527594 140500154140224 (Original Log Time 2024/08/20-04:16:30.527545) EVENT_LOG_v1 {"time_micros": 1724098590527519, "cf": "default", "job": 5951, "event": "compaction_finished", "compaction_time_micros": 5724093, "compaction_time_cpu_micros": 2183059, "output_level": 3, "num_output_files": 2, "total_output_size": 58811609, "num_input_records": 1393234, "num_output_records": 1296780, "num_subcompactions": 1, "output_compression": "Snappy", "num_single_delete_mismatches": 0, "num_single_delete_fallthrough": 0, "file_write_nanos": 50000985, "file_range_sync_nanos": 0, "file_fsync_nanos": 1739, "file_prepare_write_nanos": 7141, "lsm_state": [0, 0, 0, 2, 0, 0, 0]} 2024/08/20-04:16:30.681200 140500154140224 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":1724092920,"starts":1724098584,"executesMs":5968,"compactionJobId":5951,"attempt":0,"compactionInputRawBytes":201326656,"compactionInputZipBytes":62892291,"compactionOutputRawBytes":0,"compactionOutputZipBytes":58811609,"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":"00-4c2f272f7069421902ed5cf3e51e2ae6-69c5ea95a2d05dd4-00"}}, response = 2024/08/20-04:16:30.681325 140500154140224 INFO dcompact_worker.cpp:1456: finish /worker/dcompact-log/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/2024-08-20T02.42.00/.rocksdb/job-05951/att-00: olev 3, work 5.968 s, result 6.357 ms, install 3.349 ms, input{raw 192.000 MiB zip 59.979 MiB}