2024/08/20-04:06:30.326429 140500078605888 DEBG dcompact_worker.cpp:2211: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05331/att-00: fork to child time = 0.031847 sec 2024/08/20-04:06:30.327696 140500078605888 DEBG dcompact_worker.cpp:1011: Beg SerDeRead: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05331/att-00 2024/08/20-04:06:30.334226 140500078605888 DEBG dcompact_worker.cpp:1031: End SerDeRead: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05331/att-00 2024/08/20-04:06:30.344702 140500078605888 TRAC dcompact_worker.cpp:1081: INFO_LOG_LEVEL: rpc = INFO_LEVEL, env_var = undefined 2024/08/20-04:06:30.345177 140500078605888 [WARN] [column_family.cc:386] multiple cf_paths/db_paths and level_compaction_dynamic_level_bytes can't be used together 2024/08/20-04:06:30.399432 140500078605888 [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-05331/att-00/MANIFEST-14629260 2024/08/20-04:06:30.425688 140500078605888 [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-05331/att-00/MANIFEST-14629260 succeeded,manifest_file_number is 14629260, next_file_number is 14635208, last_sequence is 189917494835, log_number is 0,prev_log_number is 0,max_column_family is 0,min_log_number_to_keep is 14635080 2024/08/20-04:06:30.425699 140500078605888 [version_set.cc:6197] Column family [default] (ID 0), log number is 0 2024/08/20-04:06:30.425809 140500078605888 [version_set.cc:5652] Creating manifest 14635208 2024/08/20-04:06:30.462620 140500078605888 DEBG dcompact_worker.cpp:1215: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05331/att-00: bottommost_level: fake = 1, rpc = 0 2024/08/20-04:06:30.478277 140500078605888 [compaction_job.cc:2433] [default] [JOB 5331] Compacting 1@2 + 2@3 files to L3, score 0.99, subcompactions 1 : 1 2024/08/20-04:06:30.478296 140500078605888 [compaction_job.cc:2441] [default]: Compaction start summary: Base version 2785 Base level 2, inputs: [14635179(21MB)], [14635149(97MB) 14635150(38MB)] 2024/08/20-04:06:30.666014 140500078605888 [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 2024/08/20-04:06:30.666040 140500078605888 [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 2024/08/20-04:06:30.666068 140500078605888 [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 2024/08/20-04:06:30.666096 140500078605888 [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 2024/08/20-04:06:30.666111 140500078605888 [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 2024/08/20-04:06:31.376605 140500078605888 [top_zip_table_builder.cc:934] ToplingZipTableBuilder(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05331/att-00/14635209.sst) /dev/shm/ToplingTemp/Topling-159148-sbqZzc 2024/08/20-04:06:31.898232 140500078605888 [top_zip_table_builder.cc:1344] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05331/att-00/14635209.sst): first pass time = 0.52's, 257.330'MB/sec 2024/08/20-04:06:35.366833 140500078605888 [top_zip_table_builder.cc:2764] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05331/att-00/14635209.sst): old prealloc_size = 147639500, real_size = 100478960 2024/08/20-04:06:35.367060 140500078605888 [top_zip_table_builder.cc:1765] BuildReorderMap(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05331/att-00/14635209.sst): index type = NestLoudsTrieDAWG_Mixed_XL_256_32_FL, store type = DictZipBlobStore usrkeys = 197744 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 = 0.1001 GB avg-val = 654.75 avg-zval = 505.99 2024/08/20-04:06:35.367320 140500078605888 [top_zip_table_builder.cc:1295] /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05331/att-00/14635209.sst: sumWaitingMem = 0.000 GB, sumWorkingMem = 0.020 GB, reorder workingMem = 0.0004 GB, waited 0.000 sec, Key+Value = 0.134 GB 2024/08/20-04:06:35.705011 140500078605888 [top_zip_table_builder.cc:3092] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05331/att-00/14635209.sst): second pass time = 3.47's, 37.353'MB/sec, value only(96.5% of KV) wait indexing time = 0.00's, remap KeyValue time = 0.34's, 303.078'MB/sec (all stages of remap) Get OrderMap time = 0.00's, 1835.583'MB/sec (index lex order gen) rebuild zvType time = 0.24's, 0.209'MB/sec write SST data time = 0.10's, 1009.688'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 = 26987.819'MB/sec zip my value time = 3.47's, unzip length = 0.129'GB zip my value throughput = 37.353'MB/sec zip pipeline throughput = 124.735'MB/sec entries = 197744 avg-key = 24.00 avg-zkey = 1.89 avg-val = 654.75 avg-zval = 505.99 usrkeys = 197744 avg-key = 16.00 avg-zkey = 1.89 avg-val = 661.75 avg-zval = 505.99 TagRS{ kinds = RS_Key0_Tag1 bytes = 0 } TagArray{ size = 197744 bytes = 716832 } seq expand size = 1384208 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 = 0.1001 GB dict = 1.35 MB all = 0.1025 GB } UnZip/Zip{ index = 8.4840 value = 1.2940 dict = 1.00 all = 1.3094 } Zip/UnZip{ index = 0.1179 value = 0.7728 dict = 1.00 all = 0.7637 } ---------------------------- total value len = 62.427606 GB avg = 0.180 KB (by entry num) total key len = 6.793504 GB avg = 0.020 KB total ukey len = 3.192671 GB avg = 0.008 KB total ukey num = 0.389531305 Billion total entry num = 0.346409313 Billion write speed all = 1.823791775 MB/sec (with seq num) write speed all = 1.750776076 MB/sec (without seq num) 2024/08/20-04:06:35.830040 140500078605888 [compaction_job.cc:1944] [default] [JOB 5331] Generated table #14635209: 197744 keys, 102500624 bytes, temperature: kWarm 2024/08/20-04:06:35.830144 140500078605888 EVENT_LOG_v1 {"time_micros": 1724097995830084, "cf_name": "default", "job": 5331, "event": "table_file_creation", "file_number": 14635209, "file_size": 102500624, "file_checksum": "", "file_checksum_func_name": "Unknown", "smallest_seqno": 189647000998, "largest_seqno": 189917367964, "table_properties": {"data_size": 100056416, "index_size": 372928, "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": 4745856, "raw_average_key_size": 24, "raw_value_size": 129472028, "raw_average_value_size": 654, "num_data_blocks": 1, "num_entries": 197744, "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": 1724097991, "oldest_key_time": 0, "file_creation_time": 1724097991, "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": 14635209, "seqno_to_time_mapping": "N/A", "__indexstats__": "[...1 records...]"}} 2024/08/20-04:06:35.891593 140500078605888 [top_zip_table_builder.cc:934] ToplingZipTableBuilder(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05331/att-00/14635210.sst) /dev/shm/ToplingTemp/Topling-159148-uW68uf 2024/08/20-04:06:36.328092 140500078605888 [top_zip_table_builder.cc:1344] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05331/att-00/14635210.sst): first pass time = 0.44's, 131.174'MB/sec 2024/08/20-04:06:37.305263 140500078605888 [top_zip_table_builder.cc:2764] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05331/att-00/14635210.sst): old prealloc_size = 147639500, real_size = 43065824 2024/08/20-04:06:37.305397 140500078605888 [top_zip_table_builder.cc:1765] BuildReorderMap(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05331/att-00/14635210.sst): index type = NestLoudsTrieDAWG_Mixed_XL_256_32_FL, store type = DictZipBlobStore usrkeys = 84332 prefix = 4 raw-key = 0.0010 GB zip-key = 0.0002 GB avg-key = 12.00 avg-zkey = 1.96 raw-val = 0.0552 GB zip-val = 0.0429 GB avg-val = 654.86 avg-zval = 508.46 2024/08/20-04:06:37.305522 140500078605888 [top_zip_table_builder.cc:1295] /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05331/att-00/14635210.sst: sumWaitingMem = 0.000 GB, sumWorkingMem = 0.020 GB, reorder workingMem = 0.0002 GB, waited 0.000 sec, Key+Value = 0.057 GB 2024/08/20-04:06:37.443183 140500078605888 [top_zip_table_builder.cc:3092] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05331/att-00/14635210.sst): second pass time = 0.98's, 56.561'MB/sec, value only(96.5% of KV) wait indexing time = 0.00's, remap KeyValue time = 0.14's, 318.263'MB/sec (all stages of remap) Get OrderMap time = 0.00's, 1605.746'MB/sec (index lex order gen) rebuild zvType time = 0.10's, 0.203'MB/sec write SST data time = 0.03's, 1291.612'MB/sec dict compress time = 4356233619.02's, 0.000'MB/sec z-dict build time = 0.00's, sample length = 0.567'MB, throughput = 12124.981'MB/sec zip my value time = 0.98's, unzip length = 0.055'GB zip my value throughput = 56.561'MB/sec zip pipeline throughput = 112.925'MB/sec entries = 84332 avg-key = 24.00 avg-zkey = 1.96 avg-val = 654.86 avg-zval = 508.46 usrkeys = 84332 avg-key = 16.00 avg-zkey = 1.96 avg-val = 661.86 avg-zval = 508.46 TagRS{ kinds = RS_Key0_Tag1 bytes = 0 } TagArray{ size = 84332 bytes = 284640 } seq expand size = 590324 multi value expand size = 0 cnt WriteAppend = 12 UnZipSize{ index = 0.0013 GB value = 0.0552 GB dict = 0.57 MB all = 0.0572 GB } __ZipSize{ index = 0.0002 GB value = 0.0429 GB dict = 0.57 MB all = 0.0439 GB } UnZip/Zip{ index = 8.1780 value = 1.2879 dict = 1.00 all = 1.3041 } Zip/UnZip{ index = 0.1223 value = 0.7764 dict = 1.00 all = 0.7668 } ---------------------------- total value len = 62.483422 GB avg = 0.180 KB (by entry num) total key len = 6.795527 GB avg = 0.020 KB total ukey len = 3.194021 GB avg = 0.008 KB total ukey num = 0.389615637 Billion total entry num = 0.346493645 Billion write speed all = 1.825232116 MB/sec (with seq num) write speed all = 1.752201987 MB/sec (without seq num) 2024/08/20-04:06:37.553898 140500078605888 [compaction_job.cc:1944] [default] [JOB 5331] Generated table #14635210: 84332 keys, 43898675 bytes, temperature: kWarm 2024/08/20-04:06:37.553967 140500078605888 EVENT_LOG_v1 {"time_micros": 1724097997553936, "cf_name": "default", "job": 5331, "event": "table_file_creation", "file_number": 14635210, "file_size": 43898675, "file_checksum": "", "file_checksum_func_name": "Unknown", "smallest_seqno": 189813291699, "largest_seqno": 189917368005, "table_properties": {"data_size": 42879568, "index_size": 164992, "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": 2023968, "raw_average_key_size": 24, "raw_value_size": 55225763, "raw_average_value_size": 654, "num_data_blocks": 1, "num_entries": 84332, "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": 1724097995, "oldest_key_time": 0, "file_creation_time": 1724097995, "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": 14635210, "seqno_to_time_mapping": "N/A", "__indexstats__": "[...1 records...]"}} 2024/08/20-04:06:37.570128 140500078605888 [compaction_job.cc:699] job-05331: subcompact[0], size: 0.146399 G, files: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-05331/att-00 [14635209,14635210] 2024/08/20-04:06:37.596763 140500078605888 (Original Log Time 2024/08/20-04:06:30.478449) EVENT_LOG_v1 {"time_micros": 1724097990478313, "job": 5331, "event": "compaction_started", "compaction_reason": "FilesMarkedForCompaction", "files_L2": [14635179], "files_L3": [14635149, 14635150], "score": 0.989016, "input_data_size": 165510999, "oldest_snapshot_seqno": 189917494493} 2024/08/20-04:06:37.596767 140500078605888 (Original Log Time 2024/08/20-04:06:37.596451) [compaction_job.cc:2018] [default] [JOB 5331] Compacted 1@2 + 2@3 files to L3 => 146399299 bytes 2024/08/20-04:06:37.596768 140500078605888 (Original Log Time 2024/08/20-04:06:37.596710) [compaction_job.cc:1220] [default] compacted to: files[0 0 0 2 0 0 0] max score 0.01, MB/sec: 23.3 rd, 20.6 wr, level 3, files in(1, 2) out(2 +0 blob) MB in(21.3, 136.5 +0.0 blob) out(139.6 +0.0 blob), read-write-amplify(14.0) write-amplify(6.5) OK, records in: 308383, records dropped: 26307 output_compression: Snappy 2024/08/20-04:06:37.596775 140500078605888 (Original Log Time 2024/08/20-04:06:37.596746) EVENT_LOG_v1 {"time_micros": 1724097997596730, "cf": "default", "job": 5331, "event": "compaction_finished", "compaction_time_micros": 7091686, "compaction_time_cpu_micros": 1135436, "output_level": 3, "num_output_files": 2, "total_output_size": 146399299, "num_input_records": 308383, "num_output_records": 282076, "num_subcompactions": 1, "output_compression": "Snappy", "num_single_delete_mismatches": 0, "num_single_delete_fallthrough": 0, "file_write_nanos": 100499712, "file_range_sync_nanos": 0, "file_fsync_nanos": 1541, "file_prepare_write_nanos": 6142, "lsm_state": [0, 0, 0, 2, 0, 0, 0]} 2024/08/20-04:06:37.716387 140500078605888 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":1724097990,"executesMs":7263,"compactionJobId":5331,"attempt":0,"compactionInputRawBytes":209337710,"compactionInputZipBytes":165510999,"compactionOutputRawBytes":0,"compactionOutputZipBytes":146399299,"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-a467eee32176855788afa41234b49c8a-406c2e5ccfb48b83-00"}}, response = 2024/08/20-04:06:37.716467 140500078605888 INFO dcompact_worker.cpp:1456: finish /worker/dcompact-log/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/2024-08-20T02.42.00/.rocksdb/job-05331/att-00: olev 3, work 7.264 s, result 6.095 ms, install 0.341 ms, input{raw 199.640 MiB zip 157.844 MiB}