2024/08/20-14:46:10.368197 140500573775424 DEBG dcompact_worker.cpp:2211: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-35204/att-00: fork to child time = 0.046357 sec 2024/08/20-14:46:10.369216 140500573775424 DEBG dcompact_worker.cpp:1011: Beg SerDeRead: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-35204/att-00 2024/08/20-14:46:10.373880 140500573775424 DEBG dcompact_worker.cpp:1031: End SerDeRead: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-35204/att-00 2024/08/20-14:46:10.375382 140500573775424 TRAC dcompact_worker.cpp:1081: INFO_LOG_LEVEL: rpc = INFO_LEVEL, env_var = undefined 2024/08/20-14:46:10.375757 140500573775424 [WARN] [column_family.cc:386] multiple cf_paths/db_paths and level_compaction_dynamic_level_bytes can't be used together 2024/08/20-14:46:10.411821 140500573775424 [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-35204/att-00/MANIFEST-14629260 2024/08/20-14:46:10.424979 140500573775424 [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-35204/att-00/MANIFEST-14629260 succeeded,manifest_file_number is 14629260, next_file_number is 14669853, last_sequence is 190678228258, log_number is 0,prev_log_number is 0,max_column_family is 0,min_log_number_to_keep is 14669816 2024/08/20-14:46:10.424985 140500573775424 [version_set.cc:6197] Column family [default] (ID 0), log number is 0 2024/08/20-14:46:10.425041 140500573775424 [version_set.cc:5652] Creating manifest 14669853 2024/08/20-14:46:10.448809 140500573775424 DEBG dcompact_worker.cpp:1215: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-35204/att-00: bottommost_level: fake = 1, rpc = 0 2024/08/20-14:46:10.462679 140500573775424 [compaction_job.cc:2433] [default] [JOB 35204] Compacting 1@2 + 2@3 files to L3, score 0.99, subcompactions 1 : 1 2024/08/20-14:46:10.462691 140500573775424 [compaction_job.cc:2441] [default]: Compaction start summary: Base version 17996 Base level 2, inputs: [14669827(20MB)], [14669776(97MB) 14669777(46MB)] 2024/08/20-14:46:10.703867 140500573775424 [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 2024/08/20-14:46:10.703886 140500573775424 [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 2024/08/20-14:46:10.703908 140500573775424 [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 2024/08/20-14:46:10.703943 140500573775424 [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 2024/08/20-14:46:10.703956 140500573775424 [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 2024/08/20-14:46:11.672181 140500573775424 [top_zip_table_builder.cc:934] ToplingZipTableBuilder(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-35204/att-00/14669854.sst) /dev/shm/ToplingTemp/Topling-391682-66GDDn 2024/08/20-14:46:12.136965 140500573775424 [top_zip_table_builder.cc:1344] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-35204/att-00/14669854.sst): first pass time = 0.46's, 288.814'MB/sec 2024/08/20-14:46:17.031023 140500573775424 [top_zip_table_builder.cc:2764] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-35204/att-00/14669854.sst): old prealloc_size = 147639500, real_size = 100282592 2024/08/20-14:46:17.031256 140500573775424 [top_zip_table_builder.cc:1765] BuildReorderMap(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-35204/att-00/14669854.sst): index type = NestLoudsTrieDAWG_Mixed_XL_256_32_FL, store type = DictZipBlobStore usrkeys = 197700 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 = 654.90 avg-zval = 505.11 2024/08/20-14:46:17.031536 140500573775424 [top_zip_table_builder.cc:1295] /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-35204/att-00/14669854.sst: sumWaitingMem = 0.000 GB, sumWorkingMem = 0.020 GB, reorder workingMem = 0.0004 GB, waited 0.000 sec, Key+Value = 0.134 GB 2024/08/20-14:46:17.498152 140500573775424 [top_zip_table_builder.cc:3092] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-35204/att-00/14669854.sst): second pass time = 4.89's, 26.467'MB/sec, value only(96.5% of KV) wait indexing time = 0.00's, remap KeyValue time = 0.47's, 219.049'MB/sec (all stages of remap) Get OrderMap time = 0.00's, 2020.076'MB/sec (index lex order gen) rebuild zvType time = 0.36's, 0.137'MB/sec write SST data time = 0.11's, 965.162'MB/sec dict compress time = 4356233619.02's, 0.000'MB/sec z-dict build time = 0.00's, sample length = 1.348'MB, throughput = 34324.744'MB/sec zip my value time = 4.89's, unzip length = 0.129'GB zip my value throughput = 26.467'MB/sec zip pipeline throughput = 137.953'MB/sec entries = 197700 avg-key = 24.00 avg-zkey = 1.89 avg-val = 654.90 avg-zval = 505.11 usrkeys = 197700 avg-key = 16.00 avg-zkey = 1.89 avg-val = 661.90 avg-zval = 505.11 TagRS{ kinds = RS_Key0_Tag1 bytes = 0 } TagArray{ size = 197700 bytes = 741392 } seq expand size = 1383900 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 = 0.1023 GB } UnZip/Zip{ index = 8.4733 value = 1.2966 dict = 1.00 all = 1.3117 } Zip/UnZip{ index = 0.1180 value = 0.7713 dict = 1.00 all = 0.7624 } ---------------------------- total value len = 62.427607 GB avg = 0.180 KB (by entry num) total key len = 6.793502 GB avg = 0.020 KB total ukey len = 3.192671 GB avg = 0.008 KB total ukey num = 0.389531261 Billion total entry num = 0.346409269 Billion write speed all = 0.906791571 MB/sec (with seq num) write speed all = 0.870488079 MB/sec (without seq num) 2024/08/20-14:46:17.622218 140500573775424 [compaction_job.cc:1944] [default] [JOB 35204] Generated table #14669854: 197700 keys, 102325422 bytes, temperature: kWarm 2024/08/20-14:46:17.622319 140500573775424 EVENT_LOG_v1 {"time_micros": 1724136377622258, "cf_name": "default", "job": 35204, "event": "table_file_creation", "file_number": 14669854, "file_size": 102325422, "file_checksum": "", "file_checksum_func_name": "Unknown", "smallest_seqno": 189648517461, "largest_seqno": 190678136953, "table_properties": {"data_size": 99859664, "index_size": 373312, "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": 4744800, "raw_average_key_size": 24, "raw_value_size": 129473375, "raw_average_value_size": 654, "num_data_blocks": 1, "num_entries": 197700, "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": 1724136371, "oldest_key_time": 0, "file_creation_time": 1724136371, "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": 14669854, "seqno_to_time_mapping": "N/A", "__indexstats__": "[...1 records...]"}} 2024/08/20-14:46:17.705283 140500573775424 [top_zip_table_builder.cc:934] ToplingZipTableBuilder(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-35204/att-00/14669855.sst) /dev/shm/ToplingTemp/Topling-391682-Rcqaqo 2024/08/20-14:46:18.426069 140500573775424 [top_zip_table_builder.cc:1344] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-35204/att-00/14669855.sst): first pass time = 0.72's, 93.593'MB/sec 2024/08/20-14:46:19.713138 140500573775424 [top_zip_table_builder.cc:2764] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-35204/att-00/14669855.sst): old prealloc_size = 147639500, real_size = 50625936 2024/08/20-14:46:19.713270 140500573775424 [top_zip_table_builder.cc:1765] BuildReorderMap(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-35204/att-00/14669855.sst): index type = NestLoudsTrieDAWG_Mixed_XL_256_32_FL, store type = DictZipBlobStore usrkeys = 99336 prefix = 4 raw-key = 0.0012 GB zip-key = 0.0002 GB avg-key = 12.00 avg-zkey = 1.95 raw-val = 0.0651 GB zip-val = 0.0504 GB avg-val = 655.06 avg-zval = 507.44 2024/08/20-14:46:19.713407 140500573775424 [top_zip_table_builder.cc:1295] /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-35204/att-00/14669855.sst: sumWaitingMem = 0.000 GB, sumWorkingMem = 0.020 GB, reorder workingMem = 0.0002 GB, waited 0.000 sec, Key+Value = 0.067 GB 2024/08/20-14:46:20.045388 140500573775424 [top_zip_table_builder.cc:3092] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-35204/att-00/14669855.sst): second pass time = 1.29's, 50.588'MB/sec, value only(96.5% of KV) wait indexing time = 0.00's, remap KeyValue time = 0.33's, 155.356'MB/sec (all stages of remap) Get OrderMap time = 0.00's, 1841.376'MB/sec (index lex order gen) rebuild zvType time = 0.28's, 0.088'MB/sec write SST data time = 0.05's, 1014.198'MB/sec dict compress time = 4356233619.02's, 0.000'MB/sec z-dict build time = 0.00's, sample length = 0.675'MB, throughput = 12301.651'MB/sec zip my value time = 1.29's, unzip length = 0.065'GB zip my value throughput = 50.588'MB/sec zip pipeline throughput = 64.569'MB/sec entries = 99336 avg-key = 24.00 avg-zkey = 1.95 avg-val = 655.06 avg-zval = 507.44 usrkeys = 99336 avg-key = 16.00 avg-zkey = 1.95 avg-val = 662.06 avg-zval = 507.44 TagRS{ kinds = RS_Key0_Tag1 bytes = 0 } TagArray{ size = 99336 bytes = 335280 } seq expand size = 695352 multi value expand size = 0 cnt WriteAppend = 13 UnZipSize{ index = 0.0016 GB value = 0.0651 GB dict = 0.67 MB all = 0.0675 GB } __ZipSize{ index = 0.0002 GB value = 0.0504 GB dict = 0.67 MB all = 0.0516 GB } UnZip/Zip{ index = 8.2123 value = 1.2909 dict = 1.00 all = 1.3069 } Zip/UnZip{ index = 0.1218 value = 0.7747 dict = 1.00 all = 0.7652 } ---------------------------- total value len = 62.493373 GB avg = 0.180 KB (by entry num) total key len = 6.795887 GB avg = 0.020 KB total ukey len = 3.194260 GB avg = 0.008 KB total ukey num = 0.389630597 Billion total entry num = 0.346508605 Billion write speed all = 0.907654045 MB/sec (with seq num) write speed all = 0.871341354 MB/sec (without seq num) 2024/08/20-14:46:20.110481 140500573775424 [compaction_job.cc:1944] [default] [JOB 35204] Generated table #14669855: 99336 keys, 51613407 bytes, temperature: kWarm 2024/08/20-14:46:20.110551 140500573775424 EVENT_LOG_v1 {"time_micros": 1724136380110520, "cf_name": "default", "job": 35204, "event": "table_file_creation", "file_number": 14669855, "file_size": 51613407, "file_checksum": "", "file_checksum_func_name": "Unknown", "smallest_seqno": 190544034314, "largest_seqno": 190678136434, "table_properties": {"data_size": 50407360, "index_size": 193536, "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": 2384064, "raw_average_key_size": 24, "raw_value_size": 65070646, "raw_average_value_size": 655, "num_data_blocks": 1, "num_entries": 99336, "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": 1724136377, "oldest_key_time": 0, "file_creation_time": 1724136377, "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": 14669855, "seqno_to_time_mapping": "N/A", "__indexstats__": "[...1 records...]"}} 2024/08/20-14:46:20.129813 140500573775424 [compaction_job.cc:699] job-35204: subcompact[0], size: 0.153939 G, files: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-35204/att-00 [14669854,14669855] 2024/08/20-14:46:20.161001 140500573775424 (Original Log Time 2024/08/20-14:46:10.462736) EVENT_LOG_v1 {"time_micros": 1724136370462700, "job": 35204, "event": "compaction_started", "compaction_reason": "FilesMarkedForCompaction", "files_L2": [14669827], "files_L3": [14669776, 14669777], "score": 0.986085, "input_data_size": 172838847, "oldest_snapshot_seqno": 190678228129} 2024/08/20-14:46:20.161005 140500573775424 (Original Log Time 2024/08/20-14:46:20.160569) [compaction_job.cc:2018] [default] [JOB 35204] Compacted 1@2 + 2@3 files to L3 => 153938829 bytes 2024/08/20-14:46:20.161006 140500573775424 (Original Log Time 2024/08/20-14:46:20.160914) [compaction_job.cc:1220] [default] compacted to: files[0 0 0 2 0 0 0] max score 0.01, MB/sec: 17.9 rd, 15.9 wr, level 3, files in(1, 2) out(2 +0 blob) MB in(20.2, 144.6 +0.0 blob) out(146.8 +0.0 blob), read-write-amplify(15.4) write-amplify(7.3) OK, records in: 323455, records dropped: 26419 output_compression: Snappy 2024/08/20-14:46:20.161013 140500573775424 (Original Log Time 2024/08/20-14:46:20.160977) EVENT_LOG_v1 {"time_micros": 1724136380160956, "cf": "default", "job": 35204, "event": "compaction_finished", "compaction_time_micros": 9667090, "compaction_time_cpu_micros": 1331550, "output_level": 3, "num_output_files": 2, "total_output_size": 153938829, "num_input_records": 323455, "num_output_records": 297036, "num_subcompactions": 1, "output_compression": "Snappy", "num_single_delete_mismatches": 0, "num_single_delete_fallthrough": 0, "file_write_nanos": 151944666, "file_range_sync_nanos": 0, "file_fsync_nanos": 2033, "file_prepare_write_nanos": 7165, "lsm_state": [0, 0, 0, 2, 0, 0, 0]} 2024/08/20-14:46:20.307301 140500573775424 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":1724136370,"executesMs":9785,"compactionJobId":35204,"attempt":0,"compactionInputRawBytes":219620757,"compactionInputZipBytes":172838847,"compactionOutputRawBytes":0,"compactionOutputZipBytes":153938829,"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":"00-1931313d761fcacbabb6b7061cccb71c-10820b6b447829bc-00"}}, response = 2024/08/20-14:46:20.307407 140500573775424 INFO dcompact_worker.cpp:1456: finish /worker/dcompact-log/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/2024-08-20T02.42.00/.rocksdb/job-35204/att-00: olev 3, work 9.785 s, result 6.891 ms, install 0.471 ms, input{raw 209.447 MiB zip 164.832 MiB}