2024/08/20-14:05:18.502856 140500590560832 DEBG dcompact_worker.cpp:2211: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-33395/att-00: fork to child time = 0.032258 sec 2024/08/20-14:05:18.504186 140500590560832 DEBG dcompact_worker.cpp:1011: Beg SerDeRead: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-33395/att-00 2024/08/20-14:05:18.510136 140500590560832 DEBG dcompact_worker.cpp:1031: End SerDeRead: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-33395/att-00 2024/08/20-14:05:18.512129 140500590560832 TRAC dcompact_worker.cpp:1081: INFO_LOG_LEVEL: rpc = INFO_LEVEL, env_var = undefined 2024/08/20-14:05:18.512556 140500590560832 [WARN] [column_family.cc:386] multiple cf_paths/db_paths and level_compaction_dynamic_level_bytes can't be used together 2024/08/20-14:05:18.549799 140500590560832 [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-33395/att-00/MANIFEST-14629260 2024/08/20-14:05:18.615809 140500590560832 [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-33395/att-00/MANIFEST-14629260 succeeded,manifest_file_number is 14629260, next_file_number is 14667764, last_sequence is 190635648581, log_number is 0,prev_log_number is 0,max_column_family is 0,min_log_number_to_keep is 14667720 2024/08/20-14:05:18.615823 140500590560832 [version_set.cc:6197] Column family [default] (ID 0), log number is 0 2024/08/20-14:05:18.615916 140500590560832 [version_set.cc:5652] Creating manifest 14667764 2024/08/20-14:05:18.646718 140500590560832 DEBG dcompact_worker.cpp:1215: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-33395/att-00: bottommost_level: fake = 1, rpc = 0 2024/08/20-14:05:18.660842 140500590560832 [compaction_job.cc:2433] [default] [JOB 33395] Compacting 1@1 + 2@2 files to L2, score 1.00, subcompactions 1 : 1 2024/08/20-14:05:18.660863 140500590560832 [compaction_job.cc:2441] [default]: Compaction start summary: Base version 17062 Base level 1, inputs: [14667737(31MB)], [14667689(20MB) 14667690(10MB)] 2024/08/20-14:05:18.918326 140500590560832 [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 2024/08/20-14:05:18.918375 140500590560832 [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 2024/08/20-14:05:18.918399 140500590560832 [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 2024/08/20-14:05:18.918414 140500590560832 [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 2024/08/20-14:05:18.918440 140500590560832 [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 2024/08/20-14:05:19.083114 140500590560832 [top_zip_table_builder.cc:934] ToplingZipTableBuilder(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-33395/att-00/14667765.sst) /dev/shm/ToplingTemp/Topling-377833-Sum8L9 2024/08/20-14:05:19.592709 140500590560832 [top_zip_table_builder.cc:1344] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-33395/att-00/14667765.sst): first pass time = 0.51's, 131.707'MB/sec 2024/08/20-14:05:24.374075 140500590560832 [top_zip_table_builder.cc:2764] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-33395/att-00/14667765.sst): old prealloc_size = 72184660, real_size = 19590496 2024/08/20-14:05:24.374573 140500590560832 [top_zip_table_builder.cc:1765] BuildReorderMap(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-33395/att-00/14667765.sst): index type = NestLoudsTrieDAWG_Mixed_XL_256_32_FL, store type = DictZipBlobStore usrkeys = 466039 prefix = 4 raw-key = 0.0075 GB zip-key = 0.0009 GB avg-key = 16.00 avg-zkey = 1.90 raw-val = 0.0541 GB zip-val = 0.0186 GB avg-val = 116.00 avg-zval = 39.88 2024/08/20-14:05:24.375123 140500590560832 [top_zip_table_builder.cc:1295] /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-33395/att-00/14667765.sst: sumWaitingMem = 0.001 GB, sumWorkingMem = 0.020 GB, reorder workingMem = 0.0011 GB, waited 0.000 sec, Key+Value = 0.067 GB 2024/08/20-14:05:25.028269 140500590560832 [top_zip_table_builder.cc:3092] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-33395/att-00/14667765.sst): second pass time = 4.78's, 11.309'MB/sec, value only(80.6% of KV) wait indexing time = 0.00's, remap KeyValue time = 0.65's, 32.833'MB/sec (all stages of remap) Get OrderMap time = 0.00's, 1910.758'MB/sec (index lex order gen) rebuild zvType time = 0.54's, 0.214'MB/sec write SST data time = 0.11's, 196.399'MB/sec dict compress time = 4356233619.02's, 0.000'MB/sec z-dict build time = 0.00's, sample length = 0.543'MB, throughput = 16580.155'MB/sec zip my value time = 4.78's, unzip length = 0.054'GB zip my value throughput = 11.309'MB/sec zip pipeline throughput = 159.819'MB/sec entries = 466039 avg-key = 28.00 avg-zkey = 1.90 avg-val = 116.00 avg-zval = 39.88 usrkeys = 466039 avg-key = 20.00 avg-zkey = 1.90 avg-val = 123.00 avg-zval = 39.88 TagRS{ kinds = RS_Key0_Tag1 bytes = 0 } TagArray{ size = 466039 bytes = 1456384 } seq expand size = 3262273 multi value expand size = 0 cnt WriteAppend = 14 UnZipSize{ index = 0.0093 GB value = 0.0541 GB dict = 0.54 MB all = 0.0671 GB } __ZipSize{ index = 0.0009 GB value = 0.0186 GB dict = 0.54 MB all = 0.0215 GB } UnZip/Zip{ index = 10.5039 value = 2.9086 dict = 1.00 all = 3.1244 } Zip/UnZip{ index = 0.0952 value = 0.3438 dict = 1.00 all = 0.3201 } ---------------------------- total value len = 62.354072 GB avg = 0.180 KB (by entry num) total key len = 6.801807 GB avg = 0.020 KB total ukey len = 3.198828 GB avg = 0.008 KB total ukey num = 0.389799600 Billion total entry num = 0.346677608 Billion write speed all = 0.936008361 MB/sec (with seq num) write speed all = 0.898470770 MB/sec (without seq num) 2024/08/20-14:05:25.057765 140500590560832 [compaction_job.cc:1944] [default] [JOB 33395] Generated table #14667765: 466039 keys, 21479222 bytes, temperature: kWarm 2024/08/20-14:05:25.057859 140500590560832 EVENT_LOG_v1 {"time_micros": 1724133925057803, "cf_name": "default", "job": 33395, "event": "table_file_creation", "file_number": 14667765, "file_size": 21479222, "file_checksum": "", "file_checksum_func_name": "Unknown", "smallest_seqno": 190614249179, "largest_seqno": 190635543510, "table_properties": {"data_size": 18586448, "index_size": 887360, "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": 13049092, "raw_average_key_size": 28, "raw_value_size": 54059910, "raw_average_value_size": 115, "num_data_blocks": 1, "num_entries": 466039, "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": 1724133919, "oldest_key_time": 0, "file_creation_time": 1724133919, "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": 14667765, "seqno_to_time_mapping": "N/A", "__indexstats__": "[...1 records...]"}} 2024/08/20-14:05:25.088766 140500590560832 [top_zip_table_builder.cc:934] ToplingZipTableBuilder(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-33395/att-00/14667766.sst) /dev/shm/ToplingTemp/Topling-377833-P5VJDb 2024/08/20-14:05:25.533999 140500590560832 [top_zip_table_builder.cc:1344] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-33395/att-00/14667766.sst): first pass time = 0.45's, 150.498'MB/sec 2024/08/20-14:05:26.538714 140500590560832 [top_zip_table_builder.cc:2764] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-33395/att-00/14667766.sst): old prealloc_size = 72184660, real_size = 19263376 2024/08/20-14:05:26.539129 140500590560832 [top_zip_table_builder.cc:1765] BuildReorderMap(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-33395/att-00/14667766.sst): index type = NestLoudsTrieDAWG_Mixed_XL_256_32_FL, store type = DictZipBlobStore usrkeys = 465328 prefix = 4 raw-key = 0.0074 GB zip-key = 0.0009 GB avg-key = 16.00 avg-zkey = 1.90 raw-val = 0.0540 GB zip-val = 0.0183 GB avg-val = 115.98 avg-zval = 39.24 2024/08/20-14:05:26.539553 140500590560832 [top_zip_table_builder.cc:1295] /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-33395/att-00/14667766.sst: sumWaitingMem = 0.001 GB, sumWorkingMem = 0.020 GB, reorder workingMem = 0.0011 GB, waited 0.000 sec, Key+Value = 0.067 GB 2024/08/20-14:05:27.141447 140500590560832 [top_zip_table_builder.cc:3092] ToplingZipTableBuilder::Finish(/storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-33395/att-00/14667766.sst): second pass time = 1.00's, 53.766'MB/sec, value only(80.6% of KV) wait indexing time = 0.00's, remap KeyValue time = 0.60's, 35.187'MB/sec (all stages of remap) Get OrderMap time = 0.00's, 2268.853'MB/sec (index lex order gen) rebuild zvType time = 0.52's, 0.223'MB/sec write SST data time = 0.08's, 266.373'MB/sec dict compress time = 4356233619.02's, 0.000'MB/sec z-dict build time = 0.00's, sample length = 0.543'MB, throughput = 15311.395'MB/sec zip my value time = 1.00's, unzip length = 0.054'GB zip my value throughput = 53.766'MB/sec zip pipeline throughput = 88.545'MB/sec entries = 465328 avg-key = 28.00 avg-zkey = 1.90 avg-val = 115.98 avg-zval = 39.24 usrkeys = 465328 avg-key = 20.00 avg-zkey = 1.90 avg-val = 122.98 avg-zval = 39.24 TagRS{ kinds = RS_Key0_Tag1 bytes = 0 } TagArray{ size = 465328 bytes = 1512336 } seq expand size = 3257296 multi value expand size = 0 cnt WriteAppend = 13 UnZipSize{ index = 0.0093 GB value = 0.0540 GB dict = 0.54 MB all = 0.0670 GB } __ZipSize{ index = 0.0009 GB value = 0.0183 GB dict = 0.54 MB all = 0.0212 GB } UnZip/Zip{ index = 10.5031 value = 2.9555 dict = 1.00 all = 3.1592 } Zip/UnZip{ index = 0.0952 value = 0.3383 dict = 1.00 all = 0.3165 } ---------------------------- total value len = 62.411300 GB avg = 0.180 KB (by entry num) total key len = 6.814836 GB avg = 0.020 KB total ukey len = 3.208135 GB avg = 0.008 KB total ukey num = 0.390264928 Billion total entry num = 0.347142936 Billion write speed all = 0.936932474 MB/sec (with seq num) write speed all = 0.899345573 MB/sec (without seq num) 2024/08/20-14:05:27.170556 140500590560832 [compaction_job.cc:1944] [default] [JOB 33395] Generated table #14667766: 465328 keys, 21207708 bytes, temperature: kWarm 2024/08/20-14:05:27.170638 140500590560832 EVENT_LOG_v1 {"time_micros": 1724133927170593, "cf_name": "default", "job": 33395, "event": "table_file_creation", "file_number": 14667766, "file_size": 21207708, "file_checksum": "", "file_checksum_func_name": "Unknown", "smallest_seqno": 190580837683, "largest_seqno": 190635543608, "table_properties": {"data_size": 18260800, "index_size": 886080, "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": 13029184, "raw_average_key_size": 28, "raw_value_size": 53970432, "raw_average_value_size": 115, "num_data_blocks": 1, "num_entries": 465328, "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": 1724133925, "oldest_key_time": 0, "file_creation_time": 1724133925, "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": 14667766, "seqno_to_time_mapping": "N/A", "__indexstats__": "[...1 records...]"}} 2024/08/20-14:05:27.192298 140500590560832 [compaction_job.cc:699] job-33395: subcompact[0], size: 0.042687 G, files: /storage/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/mytopling/.rocksdb/job-33395/att-00 [14667765,14667766] 2024/08/20-14:05:27.214372 140500590560832 (Original Log Time 2024/08/20-14:05:18.661065) EVENT_LOG_v1 {"time_micros": 1724133918660885, "job": 33395, "event": "compaction_started", "compaction_reason": "FilesMarkedForCompaction", "files_L1": [14667737], "files_L2": [14667689, 14667690], "score": 0.999552, "input_data_size": 65622419, "oldest_snapshot_seqno": 190635647789} 2024/08/20-14:05:27.214378 140500590560832 (Original Log Time 2024/08/20-14:05:27.213816) [compaction_job.cc:2018] [default] [JOB 33395] Compacted 1@1 + 2@2 files to L2 => 42686930 bytes 2024/08/20-14:05:27.214380 140500590560832 (Original Log Time 2024/08/20-14:05:27.214285) [compaction_job.cc:1220] [default] compacted to: files[0 0 2 0 0 0 0] max score 0.02, MB/sec: 7.7 rd, 5.0 wr, level 2, files in(1, 2) out(2 +0 blob) MB in(31.8, 30.8 +0.0 blob) out(40.7 +0.0 blob), read-write-amplify(3.3) write-amplify(1.3) OK, records in: 931367, records dropped: 0 output_compression: Snappy 2024/08/20-14:05:27.214392 140500590560832 (Original Log Time 2024/08/20-14:05:27.214347) EVENT_LOG_v1 {"time_micros": 1724133927214319, "cf": "default", "job": 33395, "event": "compaction_finished", "compaction_time_micros": 8531246, "compaction_time_cpu_micros": 1858160, "output_level": 2, "num_output_files": 2, "total_output_size": 42686930, "num_input_records": 931367, "num_output_records": 931367, "num_subcompactions": 1, "output_compression": "Snappy", "num_single_delete_mismatches": 0, "num_single_delete_fallthrough": 0, "file_write_nanos": 29296968, "file_range_sync_nanos": 0, "file_fsync_nanos": 1523, "file_prepare_write_nanos": 5822, "lsm_state": [0, 0, 2, 0, 0, 0, 0]} 2024/08/20-14:05:27.345617 140500590560832 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":1724133918,"executesMs":8704,"compactionJobId":33395,"attempt":0,"compactionInputRawBytes":134108618,"compactionInputZipBytes":65622419,"compactionOutputRawBytes":0,"compactionOutputZipBytes":42686930,"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":"00-47b1765427ed3f63465ae990db488062-50a61c7ede18aeed-00"}}, response = 2024/08/20-14:05:27.345711 140500590560832 INFO dcompact_worker.cpp:1456: finish /worker/dcompact-log/nfs/i-wz9deglxdazgiryp6ltb_10.57.5.137/2024-08-20T02.42.00/.rocksdb/job-33395/att-00: olev 2, work 8.704 s, result 6.216 ms, install 0.608 ms, input{raw 127.896 MiB zip 62.582 MiB}