2024/08/20-10:17:01.788319 140500422706752 DEBG dcompact_worker.cpp:2211: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-23823/att-00: fork to child time = 0.069097 sec 2024/08/20-10:17:01.789597 140500422706752 DEBG dcompact_worker.cpp:1011: Beg SerDeRead: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-23823/att-00 2024/08/20-10:17:01.795715 140500422706752 DEBG dcompact_worker.cpp:1031: End SerDeRead: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-23823/att-00 2024/08/20-10:17:01.799342 140500422706752 TRAC dcompact_worker.cpp:1081: INFO_LOG_LEVEL: rpc = INFO_LEVEL, env_var = undefined 2024/08/20-10:17:01.799735 140500422706752 [WARN] [column_family.cc:386] multiple cf_paths/db_paths and level_compaction_dynamic_level_bytes can't be used together 2024/08/20-10:17:01.846215 140500422706752 [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-23823/att-00/MANIFEST-14629260 2024/08/20-10:17:01.861553 140500422706752 [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-23823/att-00/MANIFEST-14629260 succeeded,manifest_file_number is 14629260, next_file_number is 14656498, last_sequence is 190385354275, log_number is 0,prev_log_number is 0,max_column_family is 0,min_log_number_to_keep is 14656378 2024/08/20-10:17:01.861564 140500422706752 [version_set.cc:6197] Column family [default] (ID 0), log number is 0 2024/08/20-10:17:01.861660 140500422706752 [version_set.cc:5652] Creating manifest 14656498 2024/08/20-10:17:01.888555 140500422706752 DEBG dcompact_worker.cpp:1215: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-23823/att-00: bottommost_level: fake = 1, rpc = 0 2024/08/20-10:17:01.903575 140500422706752 [compaction_job.cc:2433] [default] [JOB 23823] Compacting 1@2 + 2@3 files to L3, score 0.94, subcompactions 1 : 1 2024/08/20-10:17:01.903595 140500422706752 [compaction_job.cc:2441] [default]: Compaction start summary: Base version 12203 Base level 2, inputs: [14656472(20MB)], [14656404(97MB) 14656405(68MB)] 2024/08/20-10:17:02.116241 140500422706752 [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 2024/08/20-10:17:02.116306 140500422706752 [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 2024/08/20-10:17:02.116337 140500422706752 [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 2024/08/20-10:17:02.116383 140500422706752 [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 2024/08/20-10:17:02.116411 140500422706752 [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 2024/08/20-10:17:02.840058 140500422706752 [top_zip_table_builder.cc:934] ToplingZipTableBuilder(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-23823/att-00/14656499.sst) /dev/shm/ToplingTemp/Topling-302815-XQLuAG 2024/08/20-10:17:03.526384 140500422706752 [top_zip_table_builder.cc:1344] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-23823/att-00/14656499.sst): first pass time = 0.69's, 195.574'MB/sec 2024/08/20-10:17:07.185680 140500422706752 [top_zip_table_builder.cc:2764] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-23823/att-00/14656499.sst): old prealloc_size = 147639500, real_size = 100343616 2024/08/20-10:17:07.185859 140500422706752 [top_zip_table_builder.cc:1765] BuildReorderMap(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-23823/att-00/14656499.sst): index type = NestLoudsTrieDAWG_Mixed_XL_256_32_FL, store type = DictZipBlobStore usrkeys = 197731 prefix = 4 raw-key = 0.0024 GB zip-key = 0.0004 GB avg-key = 12.00 avg-zkey = 1.89 raw-val = 0.1295 GB zip-val = 0.0999 GB avg-val = 654.79 avg-zval = 505.34 2024/08/20-10:17:07.186112 140500422706752 [top_zip_table_builder.cc:1295] /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-23823/att-00/14656499.sst: sumWaitingMem = 0.000 GB, sumWorkingMem = 0.020 GB, reorder workingMem = 0.0004 GB, waited 0.000 sec, Key+Value = 0.134 GB 2024/08/20-10:17:07.693469 140500422706752 [top_zip_table_builder.cc:3092] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-23823/att-00/14656499.sst): second pass time = 3.66's, 35.398'MB/sec, value only(96.5% of KV) wait indexing time = 0.00's, remap KeyValue time = 0.51's, 201.648'MB/sec (all stages of remap) Get OrderMap time = 0.00's, 2424.176'MB/sec (index lex order gen) rebuild zvType time = 0.41's, 0.121'MB/sec write SST data time = 0.10's, 1050.292'MB/sec dict compress time = 4356233619.02's, 0.000'MB/sec z-dict build time = 0.00's, sample length = 1.351'MB, throughput = 28541.036'MB/sec zip my value time = 3.66's, unzip length = 0.129'GB zip my value throughput = 35.398'MB/sec zip pipeline throughput = 124.800'MB/sec entries = 197731 avg-key = 24.00 avg-zkey = 1.89 avg-val = 654.79 avg-zval = 505.34 usrkeys = 197731 avg-key = 16.00 avg-zkey = 1.89 avg-val = 661.79 avg-zval = 505.34 TagRS{ kinds = RS_Key0_Tag1 bytes = 0 } TagArray{ size = 197731 bytes = 741504 } seq expand size = 1384117 multi value expand size = 0 cnt WriteAppend = 14 UnZipSize{ index = 0.0032 GB value = 0.1295 GB dict = 1.35 MB all = 0.1342 GB } __ZipSize{ index = 0.0004 GB value = 0.0999 GB dict = 1.35 MB all = 0.1024 GB } UnZip/Zip{ index = 8.4689 value = 1.2958 dict = 1.00 all = 1.3109 } Zip/UnZip{ index = 0.1181 value = 0.7717 dict = 1.00 all = 0.7629 } ---------------------------- total value len = 62.427606 GB avg = 0.180 KB (by entry num) total key len = 6.793503 GB avg = 0.020 KB total ukey len = 3.192671 GB avg = 0.008 KB total ukey num = 0.389531292 Billion total entry num = 0.346409300 Billion write speed all = 1.150110407 MB/sec (with seq num) write speed all = 1.104065616 MB/sec (without seq num) 2024/08/20-10:17:07.871261 140500422706752 [compaction_job.cc:1944] [default] [JOB 23823] Generated table #14656499: 197731 keys, 102389519 bytes, temperature: kWarm 2024/08/20-10:17:07.871368 140500422706752 EVENT_LOG_v1 {"time_micros": 1724120227871321, "cf_name": "default", "job": 23823, "event": "table_file_creation", "file_number": 14656499, "file_size": 102389519, "file_checksum": "", "file_checksum_func_name": "Unknown", "smallest_seqno": 189648517461, "largest_seqno": 190385236841, "table_properties": {"data_size": 99920432, "index_size": 373568, "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": 4745544, "raw_average_key_size": 24, "raw_value_size": 129472556, "raw_average_value_size": 654, "num_data_blocks": 1, "num_entries": 197731, "num_filter_entries": 0, "num_deletions": 0, "num_merge_operands": 0, "num_range_deletions": 0, "format_version": 0, "fixed_key_len": 24, "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": 1724120222, "oldest_key_time": 0, "file_creation_time": 1724120222, "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": 14656499, "seqno_to_time_mapping": "N/A", "__indexstats__": "[...1 records...]"}} 2024/08/20-10:17:07.917586 140500422706752 [top_zip_table_builder.cc:934] ToplingZipTableBuilder(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-23823/att-00/14656500.sst) /dev/shm/ToplingTemp/Topling-302815-J1ZIgG 2024/08/20-10:17:08.674146 140500422706752 [top_zip_table_builder.cc:1344] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-23823/att-00/14656500.sst): first pass time = 0.76's, 127.865'MB/sec 2024/08/20-10:17:10.170549 140500422706752 [top_zip_table_builder.cc:2764] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-23823/att-00/14656500.sst): old prealloc_size = 147639500, real_size = 72316816 2024/08/20-10:17:10.170716 140500422706752 [top_zip_table_builder.cc:1765] BuildReorderMap(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-23823/att-00/14656500.sst): index type = NestLoudsTrieDAWG_Mixed_XL_256_32_FL, store type = DictZipBlobStore usrkeys = 142492 prefix = 4 raw-key = 0.0017 GB zip-key = 0.0003 GB avg-key = 12.00 avg-zkey = 1.89 raw-val = 0.0933 GB zip-val = 0.0720 GB avg-val = 654.87 avg-zval = 505.37 2024/08/20-10:17:10.170886 140500422706752 [top_zip_table_builder.cc:1295] /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-23823/att-00/14656500.sst: sumWaitingMem = 0.000 GB, sumWorkingMem = 0.020 GB, reorder workingMem = 0.0003 GB, waited 0.000 sec, Key+Value = 0.097 GB 2024/08/20-10:17:10.412982 140500422706752 [top_zip_table_builder.cc:3092] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-23823/att-00/14656500.sst): second pass time = 1.49's, 62.442'MB/sec, value only(96.5% of KV) wait indexing time = 0.00's, remap KeyValue time = 0.24's, 304.259'MB/sec (all stages of remap) Get OrderMap time = 0.00's, 1895.435'MB/sec (index lex order gen) rebuild zvType time = 0.19's, 0.191'MB/sec write SST data time = 0.06's, 1315.141'MB/sec dict compress time = 4356233619.02's, 0.000'MB/sec z-dict build time = 0.00's, sample length = 0.982'MB, throughput = 24609.376'MB/sec zip my value time = 1.49's, unzip length = 0.093'GB zip my value throughput = 62.442'MB/sec zip pipeline throughput = 90.014'MB/sec entries = 142492 avg-key = 24.00 avg-zkey = 1.89 avg-val = 654.87 avg-zval = 505.37 usrkeys = 142492 avg-key = 16.00 avg-zkey = 1.89 avg-val = 661.87 avg-zval = 505.37 TagRS{ kinds = RS_Key0_Tag1 bytes = 0 } TagArray{ size = 142492 bytes = 498736 } seq expand size = 997444 multi value expand size = 0 cnt WriteAppend = 12 UnZipSize{ index = 0.0023 GB value = 0.0933 GB dict = 0.98 MB all = 0.0967 GB } __ZipSize{ index = 0.0003 GB value = 0.0720 GB dict = 0.98 MB all = 0.0738 GB } UnZip/Zip{ index = 8.4696 value = 1.2958 dict = 1.00 all = 1.3114 } Zip/UnZip{ index = 0.1181 value = 0.7717 dict = 1.00 all = 0.7625 } ---------------------------- total value len = 62.521918 GB avg = 0.180 KB (by entry num) total key len = 6.796923 GB avg = 0.020 KB total ukey len = 3.194951 GB avg = 0.008 KB total ukey num = 0.389673784 Billion total entry num = 0.346551792 Billion write speed all = 1.151682176 MB/sec (with seq num) write speed all = 1.105620526 MB/sec (without seq num) 2024/08/20-10:17:10.499169 140500422706752 [compaction_job.cc:1944] [default] [JOB 23823] Generated table #14656500: 142492 keys, 73764076 bytes, temperature: kWarm 2024/08/20-10:17:10.499324 140500422706752 EVENT_LOG_v1 {"time_micros": 1724120230499210, "cf_name": "default", "job": 23823, "event": "table_file_creation", "file_number": 14656500, "file_size": 73764076, "file_checksum": "", "file_checksum_func_name": "Unknown", "smallest_seqno": 190244258645, "largest_seqno": 190385236837, "table_properties": {"data_size": 72011840, "index_size": 269184, "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": 3419808, "raw_average_key_size": 24, "raw_value_size": 93314050, "raw_average_value_size": 654, "num_data_blocks": 1, "num_entries": 142492, "num_filter_entries": 0, "num_deletions": 0, "num_merge_operands": 0, "num_range_deletions": 0, "format_version": 0, "fixed_key_len": 24, "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": 1724120227, "oldest_key_time": 0, "file_creation_time": 1724120227, "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": 14656500, "seqno_to_time_mapping": "N/A", "__indexstats__": "[...1 records...]"}} 2024/08/20-10:17:10.536883 140500422706752 [compaction_job.cc:699] job-23823: subcompact[0], size: 0.176154 G, files: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-23823/att-00 [14656499,14656500] 2024/08/20-10:17:10.571511 140500422706752 (Original Log Time 2024/08/20-10:17:01.903691) EVENT_LOG_v1 {"time_micros": 1724120221903617, "job": 23823, "event": "compaction_started", "compaction_reason": "FilesMarkedForCompaction", "files_L2": [14656472], "files_L3": [14656404, 14656405], "score": 0.935593, "input_data_size": 195596560, "oldest_snapshot_seqno": 190385353486} 2024/08/20-10:17:10.571515 140500422706752 (Original Log Time 2024/08/20-10:17:10.571126) [compaction_job.cc:2018] [default] [JOB 23823] Compacted 1@2 + 2@3 files to L3 => 176153595 bytes 2024/08/20-10:17:10.571516 140500422706752 (Original Log Time 2024/08/20-10:17:10.571437) [compaction_job.cc:1220] [default] compacted to: files[0 0 0 2 0 0 0] max score 0.01, MB/sec: 22.7 rd, 20.4 wr, level 3, files in(1, 2) out(2 +0 blob) MB in(20.5, 166.0 +0.0 blob) out(168.0 +0.0 blob), read-write-amplify(17.3) write-amplify(8.2) OK, records in: 367630, records dropped: 27407 output_compression: Snappy 2024/08/20-10:17:10.571523 140500422706752 (Original Log Time 2024/08/20-10:17:10.571489) EVENT_LOG_v1 {"time_micros": 1724120230571470, "cf": "default", "job": 23823, "event": "compaction_finished", "compaction_time_micros": 8633202, "compaction_time_cpu_micros": 1328906, "output_level": 3, "num_output_files": 2, "total_output_size": 176153595, "num_input_records": 367630, "num_output_records": 340223, "num_subcompactions": 1, "output_compression": "Snappy", "num_single_delete_mismatches": 0, "num_single_delete_fallthrough": 0, "file_write_nanos": 208749159, "file_range_sync_nanos": 0, "file_fsync_nanos": 1505, "file_prepare_write_nanos": 6761, "lsm_state": [0, 0, 0, 2, 0, 0, 0]} 2024/08/20-10:17:10.697595 140500422706752 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":1724120221,"executesMs":8776,"compactionJobId":23823,"attempt":0,"compactionInputRawBytes":249555465,"compactionInputZipBytes":195596560,"compactionOutputRawBytes":0,"compactionOutputZipBytes":176153595,"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":"00-6327489934af351632d310918426b9b5-f75122c5b54f8cfe-00"}}, response = 2024/08/20-10:17:10.697691 140500422706752 INFO dcompact_worker.cpp:1456: finish /worker/dcompact-log/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/2024-08-20T02.42.00/.rocksdb/job-23823/att-00: olev 3, work 8.776 s, result 6.042 ms, install 0.417 ms, input{raw 237.995 MiB zip 186.535 MiB}