2024/08/20-12:04:57.760978 140500372350528 DEBG dcompact_worker.cpp:2211: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-28343/att-00: fork to child time = 0.027488 sec 2024/08/20-12:04:57.762240 140500372350528 DEBG dcompact_worker.cpp:1011: Beg SerDeRead: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-28343/att-00 2024/08/20-12:04:57.768393 140500372350528 DEBG dcompact_worker.cpp:1031: End SerDeRead: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-28343/att-00 2024/08/20-12:04:57.770742 140500372350528 TRAC dcompact_worker.cpp:1081: INFO_LOG_LEVEL: rpc = INFO_LEVEL, env_var = undefined 2024/08/20-12:04:57.771135 140500372350528 [WARN] [column_family.cc:386] multiple cf_paths/db_paths and level_compaction_dynamic_level_bytes can't be used together 2024/08/20-12:04:57.809157 140500372350528 [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-28343/att-00/MANIFEST-14629260 2024/08/20-12:04:57.837934 140500372350528 [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-28343/att-00/MANIFEST-14629260 succeeded,manifest_file_number is 14629260, next_file_number is 14661748, last_sequence is 190506447962, log_number is 0,prev_log_number is 0,max_column_family is 0,min_log_number_to_keep is 14661486 2024/08/20-12:04:57.837948 140500372350528 [version_set.cc:6197] Column family [default] (ID 0), log number is 0 2024/08/20-12:04:57.838033 140500372350528 [version_set.cc:5652] Creating manifest 14661748 2024/08/20-12:04:57.863854 140500372350528 DEBG dcompact_worker.cpp:1215: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-28343/att-00: bottommost_level: fake = 1, rpc = 0 2024/08/20-12:04:57.877298 140500372350528 [compaction_job.cc:2433] [default] [JOB 28343] Compacting 1@2 + 2@3 files to L3, score 0.95, subcompactions 1 : 1 2024/08/20-12:04:57.877313 140500372350528 [compaction_job.cc:2441] [default]: Compaction start summary: Base version 14483 Base level 2, inputs: [14661718(19MB)], [14661678(97MB) 14661679(19MB)] 2024/08/20-12:04:58.055516 140500372350528 [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 2024/08/20-12:04:58.055545 140500372350528 [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 2024/08/20-12:04:58.055570 140500372350528 [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 2024/08/20-12:04:58.055587 140500372350528 [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 2024/08/20-12:04:58.055601 140500372350528 [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 2024/08/20-12:04:59.076153 140500372350528 [top_zip_table_builder.cc:934] ToplingZipTableBuilder(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-28343/att-00/14661749.sst) /dev/shm/ToplingTemp/Topling-337942-64wnYK 2024/08/20-12:04:59.400626 140500372350528 [top_zip_table_builder.cc:1344] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-28343/att-00/14661749.sst): first pass time = 0.32's, 413.719'MB/sec 2024/08/20-12:05:02.871418 140500372350528 [top_zip_table_builder.cc:2764] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-28343/att-00/14661749.sst): old prealloc_size = 147639500, real_size = 100236112 2024/08/20-12:05:02.871640 140500372350528 [top_zip_table_builder.cc:1765] BuildReorderMap(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-28343/att-00/14661749.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 = 1.91 raw-val = 0.1295 GB zip-val = 0.0998 GB avg-val = 654.90 avg-zval = 504.85 2024/08/20-12:05:02.871905 140500372350528 [top_zip_table_builder.cc:1295] /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-28343/att-00/14661749.sst: sumWaitingMem = 0.000 GB, sumWorkingMem = 0.020 GB, reorder workingMem = 0.0004 GB, waited 0.000 sec, Key+Value = 0.134 GB 2024/08/20-12:05:03.169146 140500372350528 [top_zip_table_builder.cc:3092] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-28343/att-00/14661749.sst): second pass time = 3.47's, 37.325'MB/sec, value only(96.5% of KV) wait indexing time = 0.00's, remap KeyValue time = 0.30's, 343.526'MB/sec (all stages of remap) Get OrderMap time = 0.00's, 1897.457'MB/sec (index lex order gen) rebuild zvType time = 0.22's, 0.228'MB/sec write SST data time = 0.08's, 1272.144'MB/sec dict compress time = 4356233619.02's, 0.000'MB/sec z-dict build time = 0.00's, sample length = 1.346'MB, throughput = 32262.596'MB/sec zip my value time = 3.47's, unzip length = 0.129'GB zip my value throughput = 37.325'MB/sec zip pipeline throughput = 121.683'MB/sec entries = 197700 avg-key = 24.00 avg-zkey = 1.91 avg-val = 654.90 avg-zval = 504.85 usrkeys = 197700 avg-key = 16.00 avg-zkey = 1.91 avg-val = 661.90 avg-zval = 504.85 TagRS{ kinds = RS_Key0_Tag1 bytes = 0 } TagArray{ size = 197700 bytes = 741392 } seq expand size = 1383900 multi value expand size = 0 cnt WriteAppend = 13 UnZipSize{ index = 0.0032 GB value = 0.1295 GB dict = 1.35 MB all = 0.1342 GB } __ZipSize{ index = 0.0004 GB value = 0.0998 GB dict = 1.35 MB all = 0.1023 GB } UnZip/Zip{ index = 8.3970 value = 1.2972 dict = 1.00 all = 1.3123 } Zip/UnZip{ index = 0.1191 value = 0.7709 dict = 1.00 all = 0.7620 } ---------------------------- 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 = 1.038389850 MB/sec (with seq num) write speed all = 0.996817807 MB/sec (without seq num) 2024/08/20-12:05:03.296302 140500372350528 [compaction_job.cc:1944] [default] [JOB 28343] Generated table #14661749: 197700 keys, 102276755 bytes, temperature: kWarm 2024/08/20-12:05:03.296402 140500372350528 EVENT_LOG_v1 {"time_micros": 1724126703296342, "cf_name": "default", "job": 28343, "event": "table_file_creation", "file_number": 14661749, "file_size": 102276755, "file_checksum": "", "file_checksum_func_name": "Unknown", "smallest_seqno": 189648517461, "largest_seqno": 190506301723, "table_properties": {"data_size": 99809792, "index_size": 376704, "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": 129473442, "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": 1724126699, "oldest_key_time": 0, "file_creation_time": 1724126699, "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": 14661749, "seqno_to_time_mapping": "N/A", "__indexstats__": "[...1 records...]"}} 2024/08/20-12:05:03.373247 140500372350528 [top_zip_table_builder.cc:934] ToplingZipTableBuilder(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-28343/att-00/14661750.sst) /dev/shm/ToplingTemp/Topling-337942-ebdlKM 2024/08/20-12:05:03.737065 140500372350528 [top_zip_table_builder.cc:1344] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-28343/att-00/14661750.sst): first pass time = 0.36's, 87.498'MB/sec 2024/08/20-12:05:04.240453 140500372350528 [top_zip_table_builder.cc:2764] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-28343/att-00/14661750.sst): old prealloc_size = 147639500, real_size = 23980672 2024/08/20-12:05:04.240568 140500372350528 [top_zip_table_builder.cc:1765] BuildReorderMap(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-28343/att-00/14661750.sst): index type = NestLoudsTrieDAWG_Mixed_XL_256_32_FL, store type = DictZipBlobStore usrkeys = 46884 prefix = 4 raw-key = 0.0006 GB zip-key = 0.0001 GB avg-key = 12.00 avg-zkey = 2.01 raw-val = 0.0307 GB zip-val = 0.0239 GB avg-val = 654.88 avg-zval = 509.23 2024/08/20-12:05:04.240658 140500372350528 [top_zip_table_builder.cc:1295] /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-28343/att-00/14661750.sst: sumWaitingMem = 0.000 GB, sumWorkingMem = 0.020 GB, reorder workingMem = 0.0001 GB, waited 0.000 sec, Key+Value = 0.032 GB 2024/08/20-12:05:04.308701 140500372350528 [top_zip_table_builder.cc:3092] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-28343/att-00/14661750.sst): second pass time = 0.50's, 61.104'MB/sec, value only(96.5% of KV) wait indexing time = 0.00's, remap KeyValue time = 0.07's, 358.199'MB/sec (all stages of remap) Get OrderMap time = 0.00's, 1075.913'MB/sec (index lex order gen) rebuild zvType time = 0.05's, 0.232'MB/sec write SST data time = 0.02's, 1379.770'MB/sec dict compress time = 4356233619.02's, 0.000'MB/sec z-dict build time = 0.00's, sample length = 0.314'MB, throughput = 8499.053'MB/sec zip my value time = 0.50's, unzip length = 0.031'GB zip my value throughput = 61.104'MB/sec zip pipeline throughput = 61.104'MB/sec entries = 46884 avg-key = 24.00 avg-zkey = 2.01 avg-val = 654.88 avg-zval = 509.23 usrkeys = 46884 avg-key = 16.00 avg-zkey = 2.01 avg-val = 661.88 avg-zval = 509.23 TagRS{ kinds = RS_Key0_Tag1 bytes = 0 } TagArray{ size = 46884 bytes = 158256 } seq expand size = 328188 multi value expand size = 0 cnt WriteAppend = 106 UnZipSize{ index = 0.0008 GB value = 0.0307 GB dict = 0.31 MB all = 0.0318 GB } __ZipSize{ index = 0.0001 GB value = 0.0239 GB dict = 0.31 MB all = 0.0244 GB } UnZip/Zip{ index = 7.9735 value = 1.2860 dict = 1.00 all = 1.3022 } Zip/UnZip{ index = 0.1254 value = 0.7776 dict = 1.00 all = 0.7680 } ---------------------------- total value len = 62.458639 GB avg = 0.180 KB (by entry num) total key len = 6.794628 GB avg = 0.020 KB total ukey len = 3.193421 GB avg = 0.008 KB total ukey num = 0.389578145 Billion total entry num = 0.346456153 Billion write speed all = 1.038854477 MB/sec (with seq num) write speed all = 0.997277518 MB/sec (without seq num) 2024/08/20-12:05:04.344608 140500372350528 [compaction_job.cc:1944] [default] [JOB 28343] Generated table #14661750: 46884 keys, 24442866 bytes, temperature: kWarm 2024/08/20-12:05:04.344671 140500372350528 EVENT_LOG_v1 {"time_micros": 1724126704344639, "cf_name": "default", "job": 28343, "event": "table_file_creation", "file_number": 14661750, "file_size": 24442866, "file_checksum": "", "file_checksum_func_name": "Unknown", "smallest_seqno": 190397636627, "largest_seqno": 190506301287, "table_properties": {"data_size": 23874672, "index_size": 94080, "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": 1125216, "raw_average_key_size": 24, "raw_value_size": 30703390, "raw_average_value_size": 654, "num_data_blocks": 1, "num_entries": 46884, "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": 1724126703, "oldest_key_time": 0, "file_creation_time": 1724126703, "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": 14661750, "seqno_to_time_mapping": "N/A", "__indexstats__": "[...1 records...]"}} 2024/08/20-12:05:04.355506 140500372350528 [compaction_job.cc:699] job-28343: subcompact[0], size: 0.126720 G, files: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-28343/att-00 [14661749,14661750] 2024/08/20-12:05:04.379867 140500372350528 (Original Log Time 2024/08/20-12:04:57.877362) EVENT_LOG_v1 {"time_micros": 1724126697877323, "job": 28343, "event": "compaction_started", "compaction_reason": "FilesMarkedForCompaction", "files_L2": [14661718], "files_L3": [14661678, 14661679], "score": 0.952194, "input_data_size": 143944737, "oldest_snapshot_seqno": 190506447769} 2024/08/20-12:05:04.379870 140500372350528 (Original Log Time 2024/08/20-12:05:04.379493) [compaction_job.cc:2018] [default] [JOB 28343] Compacted 1@2 + 2@3 files to L3 => 126719621 bytes 2024/08/20-12:05:04.379872 140500372350528 (Original Log Time 2024/08/20-12:05:04.379803) [compaction_job.cc:1220] [default] compacted to: files[0 0 0 2 0 0 0] max score 0.00, MB/sec: 22.2 rd, 19.6 wr, level 3, files in(1, 2) out(2 +0 blob) MB in(19.8, 117.4 +0.0 blob) out(120.8 +0.0 blob), read-write-amplify(13.0) write-amplify(6.1) OK, records in: 267973, records dropped: 23389 output_compression: Snappy 2024/08/20-12:05:04.379878 140500372350528 (Original Log Time 2024/08/20-12:05:04.379847) EVENT_LOG_v1 {"time_micros": 1724126704379827, "cf": "default", "job": 28343, "event": "compaction_finished", "compaction_time_micros": 6478155, "compaction_time_cpu_micros": 884776, "output_level": 3, "num_output_files": 2, "total_output_size": 126719621, "num_input_records": 267973, "num_output_records": 244584, "num_subcompactions": 1, "output_compression": "Snappy", "num_single_delete_mismatches": 0, "num_single_delete_fallthrough": 0, "file_write_nanos": 78648254, "file_range_sync_nanos": 0, "file_fsync_nanos": 1903, "file_prepare_write_nanos": 8464, "lsm_state": [0, 0, 0, 2, 0, 0, 0]} 2024/08/20-12:05:04.500417 140500372350528 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":1724126697,"executesMs":6612,"compactionJobId":28343,"attempt":0,"compactionInputRawBytes":181947353,"compactionInputZipBytes":143944737,"compactionOutputRawBytes":0,"compactionOutputZipBytes":126719621,"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":"00-5273cfae0b9419b1022650b66b133d73-658b3c406d4afcf4-00"}}, response = 2024/08/20-12:05:04.500525 140500372350528 INFO dcompact_worker.cpp:1456: finish /worker/dcompact-log/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/2024-08-20T02.42.00/.rocksdb/job-28343/att-00: olev 3, work 6.612 s, result 6.095 ms, install 0.406 ms, input{raw 173.519 MiB zip 137.276 MiB}