
```
.../dbname/tablename$ ls -l
total 76600
-rw-r----- 1 clickhouse clickhouse 1175 Jul 9 06:41 000008.sst
-rw-r----- 1 clickhouse clickhouse 80 Jul 9 07:16 000015.log
-rw-r----- 1 clickhouse clickhouse 16 Jul 9 06:42 CURRENT
-rw-r----- 1 clickhouse clickhouse 37 Jul 9 06:38 IDENTITY
-rw-r----- 1 clickhouse clickhouse 0 Jul 9 06:38 LOCK
-rw-r----- 1 clickhouse clickhouse 64020 Jul 9 08:02 LOG
-rw-r----- 1 clickhouse clickhouse 23819 Jul 9 06:40 LOG.old.1625838114977096
-rw-r----- 1 clickhouse clickhouse 27520 Jul 9 06:42 LOG.old.1625838154318798
-rw-r----- 1 clickhouse clickhouse 137 Jul 9 06:42 MANIFEST-000014
-rw-r----- 1 clickhouse clickhouse 6075 Jul 9 06:41 OPTIONS-000012
-rw-r----- 1 clickhouse clickhouse 6075 Jul 9 06:42 OPTIONS-000017
```

Part of the LOG file:

```
2021/07/09-06:42:34.319227 7f7384cf1000 RocksDB version: 6.15.0
2021/07/09-06:42:34.319295 7f7384cf1000 Git sha rocksdb_build_git_sha:@54a0decabbcf4c0bb5cf7befa9c597f28289bff5@
2021/07/09-06:42:34.319298 7f7384cf1000 Compile date Jun 2 2021
2021/07/09-06:42:34.319377 7f7384cf1000 DB SUMMARY
2021/07/09-06:42:34.319380 7f7384cf1000 DB Session ID: AN44HOX7JE4ELDVCK4QB
2021/07/09-06:42:34.319441 7f7384cf1000 CURRENT file: CURRENT
2021/07/09-06:42:34.319444 7f7384cf1000 IDENTITY file: IDENTITY
2021/07/09-06:42:34.319449 7f7384cf1000 MANIFEST file: MANIFEST-000009 size: 137 Bytes
2021/07/09-06:42:34.319452 7f7384cf1000 SST files in /data/clickhouse/data/Alloy/TableVersions/ dir, Total Num: 1, files: 000008.s
st
2021/07/09-06:42:34.319481 7f7384cf1000 Write Ahead Log file in /data/clickhouse/data/Alloy/TableVersions: 000010.log size: 0 ;
2021/07/09-06:42:34.319484 7f7384cf1000 Options.error_if_exists: 0
2021/07/09-06:42:34.319485 7f7384cf1000 Options.create_if_missing: 1
2021/07/09-06:42:34.319486 7f7384cf1000 Options.paranoid_checks: 1
2021/07/09-06:42:34.319488 7f7384cf1000 Options.track_and_verify_wals_in_manifest: 0
2021/07/09-06:42:34.319489 7f7384cf1000 Options.env: 0x13ca9be8
2021/07/09-06:42:34.319491 7f7384cf1000 Options.fs: Posix File System
2021/07/09-06:42:34.319492 7f7384cf1000 Options.info_log: 0x7f73a7555c60
2021/07/09-06:42:34.319493 7f7384cf1000 Options.max_file_opening_threads: 16
2021/07/09-06:42:34.319494 7f7384cf1000 Options.statistics: (nil)
2021/07/09-06:42:34.319496 7f7384cf1000 Options.use_fsync: 0
2021/07/09-06:42:34.319497 7f7384cf1000 Options.max_log_file_size: 0

...

...

2021/07/09-06:42:34.333954 7f7376feb000 [db/db_impl/db_impl.cc:902] ------- DUMPING STATS -------
2021/07/09-06:42:34.333976 7f7376feb000 [db/db_impl/db_impl.cc:903]
** DB Stats **
Uptime(secs): 0.0 total, 0.0 interval
Cumulative writes: 0 writes, 0 keys, 0 commit groups, 0.0 writes per commit group, ingest: 0.00 GB, 0.00 MB/s
Cumulative WAL: 0 writes, 0 syncs, 0.00 writes per sync, written: 0.00 GB, 0.00 MB/s
Cumulative stall: 00:00:0.000 H:M:S, 0.0 percent
Interval writes: 0 writes, 0 keys, 0 commit groups, 0.0 writes per commit group, ingest: 0.00 MB, 0.00 MB/s
Interval WAL: 0 writes, 0 syncs, 0.00 writes per sync, written: 0.00 MB, 0.00 MB/s
Interval stall: 00:00:0.000 H:M:S, 0.0 percent

** Compaction Stats [default] **
Level Files Size Score Read(GB) Rn(GB) Rnp1(GB) Write(GB) Wnew(GB) Moved(GB) W-Amp Rd(MB/s) Wr(MB/s) Comp(sec) CompMergeCPU(sec) Comp(cnt) Avg(sec) KeyIn KeyDrop
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------
L0 1/0 1.15 KB 0.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.00 0.00 0 0.000 0 0
Sum 1/0 1.15 KB 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.00 0.00 0 0.000 0 0
Int 0/0 0.00 KB 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.00 0.00 0 0.000 0 0

** Compaction Stats [default] **
Priority Files Size Score Read(GB) Rn(GB) Rnp1(GB) Write(GB) Wnew(GB) Moved(GB) W-Amp Rd(MB/s) Wr(MB/s) Comp(sec) CompMergeCPU(sec) Comp(cnt) Avg(sec) KeyIn KeyDrop
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Uptime(secs): 0.0 total, 0.0 interval

....
```

It looks like we need to control it via:
https://github.com/facebook/rocksdb/blob/5afd1e309c6959bf192393e4957e0c83234db4fe/include/rocksdb/options.h#L495-L499

and maybe forward those logs to the main clickhouse logs? 
#include <Storages/RocksDB/StorageEmbeddedRocksDB.h>
#include <Storages/RocksDB/EmbeddedRocksDBBlockOutputStream.h>
#include <Storages/RocksDB/EmbeddedRocksDBBlockInputStream.h>
#include <DataTypes/DataTypesNumber.h>
#include <Storages/SelectQueryInfo.h>
#include <Storages/StorageFactory.h>
#include <Parsers/ASTSelectQuery.h>
#include <Parsers/ASTIdentifier.h>
#include <Parsers/ASTLiteral.h>
#include <Parsers/ASTSubquery.h>
#include <Parsers/ASTExpressionList.h>
#include <Parsers/ASTFunction.h>
#include <Parsers/ASTCreateQuery.h>
#include <IO/WriteBufferFromString.h>
#include <IO/ReadBufferFromString.h>
#include <Processors/Sources/SourceFromInputStream.h>
#include <Processors/Pipe.h>
#include <Interpreters/Context.h>
#include <Interpreters/Set.h>
#include <Interpreters/PreparedSets.h>
#include <Interpreters/TreeRewriter.h>
#include <Interpreters/convertFieldToType.h>
#include <Poco/Logger.h>
#include <common/logger_useful.h>
#include <rocksdb/db.h>
#include <rocksdb/table.h>
#include <filesystem>