Inappropriate wording in Chinese. Even '罗林位图'(direct transliteration) is better than '呻吟声'(means sound of moaning).
As for the Roaring Bitmap is a well-known novel approach in the context of data structure that outperforms the other conventional compression bitmaps (by the year 2018), it can be kept as is.
Fix query cancelation in case of Distributed queries with LIMIT (when
the initator does not required to read all the data), since this cannot
be done until the query was sent (from the Query packet up to the empty
data Block), otherwise you will get:
2020.11.21 21:47:23.297161 [ 184 ] {} <Error> TCPHandler: Code: 101, e.displayText() = DB::Exception: Unexpected packet Data received from client, Stack trace:
0. /build/obj-x86_64-linux-gnu/../contrib/libcxx/include/exception:129: Poco::Exception::Exception(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, int) @ 0x244f5bc9 in /usr/bin/clickhouse
1. /build/obj-x86_64-linux-gnu/../src/Common/Exception.cpp:40: DB::Exception::Exception(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, int) @ 0xa14a421 in /usr/bin/clickhouse
2. /build/obj-x86_64-linux-gnu/../src/Common/NetException.h:0: DB::TCPHandler::receiveUnexpectedData() @ 0x1e032a74 in /usr/bin/clickhouse
3. /build/obj-x86_64-linux-gnu/../src/Server/TCPHandler.cpp:824: DB::TCPHandler::receivePacket() @ 0x1e024685 in /usr/bin/clickhouse
4. /build/obj-x86_64-linux-gnu/../src/Server/TCPHandler.cpp:178: DB::TCPHandler::runImpl() @ 0x1e01736b in /usr/bin/clickhouse
5. /build/obj-x86_64-linux-gnu/../src/Server/TCPHandler.cpp:0: DB::TCPHandler::run() @ 0x1e035c1b in /usr/bin/clickhouse
6. /build/obj-x86_64-linux-gnu/../contrib/poco/Net/src/TCPServerConnection.cpp:57: Poco::Net::TCPServerConnection::start() @ 0x243559cf in /usr/bin/clickhouse
7. /build/obj-x86_64-linux-gnu/../contrib/poco/Net/src/TCPServerDispatcher.cpp:0: Poco::Net::TCPServerDispatcher::run() @ 0x24356521 in /usr/bin/clickhouse
8. /build/obj-x86_64-linux-gnu/../contrib/poco/Foundation/src/ThreadPool.cpp:0: Poco::PooledThread::run() @ 0x24609175 in /usr/bin/clickhouse
9. /build/obj-x86_64-linux-gnu/../contrib/poco/Foundation/src/Thread_POSIX.cpp:0: Poco::ThreadImpl::runnableEntry(void*) @ 0x24603cb7 in /usr/bin/clickhouse
10. start_thread @ 0x9669 in /usr/lib/x86_64-linux-gnu/libpthread-2.30.so
11. __clone @ 0x1222b3 in /usr/lib/x86_64-linux-gnu/libc-2.30.so
Since if the connection will be closed (by some reason), then the
setting will not be applied after transparent reconnect (since only
native clickhouse-client can do this, since it parses the query, but
perf tests uses python driver).
Just use inplace SETTINGS clause or <settings>.
So now you will get additional message:
2020.11.21 13:37:15.429767 [ 380840 ] {47e1540d-f4cd-4f2f-9383-f1216e8328dc} <Trace> StorageDistributed (dist_01247): (127.0.0.2:9000) Cancelling query
Otherwise flaky tests will run then both, not a problem, but this is
just to trigger flaky check, since there is some tricky issue [1]:
2020-11-20 00:35:51 01247_optimize_distributed_group_by_sharding_key: [ FAIL ] 0.67 sec. - return code 101
2020-11-20 00:35:51 Received exception from server (version 20.12.1):
2020-11-20 00:35:51 Code: 101. DB::Exception: Received from localhost:9000. DB::Exception: Received from 127.0.0.2:9000. DB::Exception: Unexpected packet Data received from client.
[1]: https://clickhouse-test-reports.s3.yandex.net/16996/8d71564056925df1415880f382aaa169cbdf37b0/functional_stateless_tests_flaky_check_(address)/test_run.txt.out.log
