--details-enable
By default, statistics of the metric_types table, tablet and cdc are summed by metric_type and statistic name. This is done to reduce the amount of output in an as sensible way as possible without harming facts and truth.
However, sometimes it is necessary to split up the statistics per metric_type to understand metrics about specific table, tablet or cdc metric_types statistics. This can be done using the --details-enable switch. This switch introduces a few more columns in the output to detail the table, tablet or cdc metric type statistics.
This is how the regular output looks like:
yb_stats --snapshot-diff -b 0 -e 1 --hostname-match 82:7000 --stat-name-match rocksdb
192.168.66.81:7000 tablet rocksdb_block_cache_bytes_read 11760999 bytes 865351.998 /s
192.168.66.81:7000 tablet rocksdb_block_cache_data_hit 255 blocks 18.762 /s
192.168.66.81:7000 tablet rocksdb_block_cache_hit 548 blocks 40.321 /s
192.168.66.81:7000 tablet rocksdb_block_cache_index_hit 293 blocks 21.558 /s
192.168.66.81:7000 tablet rocksdb_block_cache_single_touch_bytes_read 11760999 bytes 865351.998 /s
192.168.66.81:7000 tablet rocksdb_block_cache_single_touch_hit 548 blocks 40.321 /s
192.168.66.81:7000 tablet rocksdb_db_iter_bytes_read 1695826 bytes 124775.660 /s
192.168.66.81:7000 tablet rocksdb_no_table_cache_iterators 193 iters 14.201 /s
192.168.66.81:7000 tablet rocksdb_number_db_next 2783 keys 204.768 /s
192.168.66.81:7000 tablet rocksdb_number_db_next_found 2783 keys 204.768 /s
192.168.66.81:7000 tablet rocksdb_number_db_seek 268 keys 19.719 /s
192.168.66.81:7000 tablet rocksdb_number_db_seek_found 257 keys 18.910 /s
192.168.66.81:7000 tablet rocksdb_number_superversion_acquires 3 nr 0.221 /s
This is filtered down to statistics that are happening on the tablet metric type.
This is how that output looks like when --details-enable is added:
yb_stats --snapshot-diff -b 0 -e 1 --hostname-match 82:7000 --stat-name-match rocksdb --details-enable
192.168.66.81:7000 tablet 00000000000000000000000000000000 sys.catalog rocksdb_block_cache_bytes_read 11760999 bytes 865351.998 /s
192.168.66.81:7000 tablet 00000000000000000000000000000000 sys.catalog rocksdb_block_cache_data_hit 255 blocks 18.762 /s
192.168.66.81:7000 tablet 00000000000000000000000000000000 sys.catalog rocksdb_block_cache_hit 548 blocks 40.321 /s
192.168.66.81:7000 tablet 00000000000000000000000000000000 sys.catalog rocksdb_block_cache_index_hit 293 blocks 21.558 /s
192.168.66.81:7000 tablet 00000000000000000000000000000000 sys.catalog rocksdb_block_cache_single_touch_bytes_read 11760999 bytes 865351.998 /s
192.168.66.81:7000 tablet 00000000000000000000000000000000 sys.catalog rocksdb_block_cache_single_touch_hit 548 blocks 40.321 /s
192.168.66.81:7000 tablet 00000000000000000000000000000000 sys.catalog rocksdb_db_iter_bytes_read 1695826 bytes 124775.660 /s
192.168.66.81:7000 tablet 00000000000000000000000000000000 sys.catalog rocksdb_no_table_cache_iterators 193 iters 14.201 /s
192.168.66.81:7000 tablet 00000000000000000000000000000000 sys.catalog rocksdb_number_db_next 2783 keys 204.768 /s
192.168.66.81:7000 tablet 00000000000000000000000000000000 sys.catalog rocksdb_number_db_next_found 2783 keys 204.768 /s
192.168.66.81:7000 tablet 00000000000000000000000000000000 sys.catalog rocksdb_number_db_seek 268 keys 19.719 /s
192.168.66.81:7000 tablet 00000000000000000000000000000000 sys.catalog rocksdb_number_db_seek_found 257 keys 18.910 /s
192.168.66.81:7000 tablet 00000000000000000000000000000000 sys.catalog rocksdb_number_superversion_acquires 3 nr 0.221 /s
In this case, the statistics were generated by a single tablet. However if multiple tablets were involved, the statistics for all of these would be shown.
The --details-enable switch introduces a couple of extra columns:
- A column for the UUID or number of the metric object
- A column that shows the namespace and the object name.