内省函数
您可以使用本章中描述的函数来内省 ELF 和 DWARF 以进行查询分析。
注意
这些函数速度较慢，并且可能存在安全隐患。
为了使内省函数正常运行
安装
clickhouse-common-static-dbg包。将 allow_introspection_functions 设置设置为 1。
For security reasons introspection functions are disabled by default.
ClickHouse 将分析器报告保存到 trace_log 系统表中。确保已正确配置该表和分析器。
addressToLine
将 ClickHouse 服务器进程内的虚拟内存地址转换为 ClickHouse 源代码中的文件名和行号。
如果您使用的是官方 ClickHouse 包，则需要安装 clickhouse-common-static-dbg 包。
语法
addressToLine(address_of_binary_instruction)
参数
address_of_binary_instruction(UInt64) — 正在运行的进程中指令的地址。
返回值
- 源代码文件名和此文件中的行号，以冒号分隔。例如，
/build/obj-x86_64-linux-gnu/../src/Common/ThreadPool.cpp:199，其中199是行号。 - 如果函数找不到调试信息，则为二进制文件的名称。
- 如果地址无效，则为空字符串。
类型：String。
示例
启用内省函数
SET allow_introspection_functions=1;
从 trace_log 系统表中选择第一个字符串
SELECT * FROM system.trace_log LIMIT 1 \G;
Row 1:
──────
event_date: 2019-11-19
event_time: 2019-11-19 18:57:23
revision: 54429
timer_type: Real
thread_number: 48
query_id: 421b6855-1858-45a5-8f37-f383409d6d72
trace: [140658411141617,94784174532828,94784076370703,94784076372094,94784076361020,94784175007680,140658411116251,140658403895439]
trace 字段包含采样时堆栈跟踪。
获取单个地址的源代码文件名和行号
SELECT addressToLine(94784076370703) \G;
Row 1:
──────
addressToLine(94784076370703): /build/obj-x86_64-linux-gnu/../src/Common/ThreadPool.cpp:199
将函数应用于整个堆栈跟踪
SELECT
arrayStringConcat(arrayMap(x -> addressToLine(x), trace), '\n') AS trace_source_code_lines
FROM system.trace_log
LIMIT 1
\G
arrayMap 函数允许使用 addressToLine 函数处理 trace 数组的每个元素。您可以在输出的 trace_source_code_lines 列中看到此处理的结果。
Row 1:
──────
trace_source_code_lines: /lib/x86_64-linux-gnu/libpthread-2.27.so
/usr/lib/debug/usr/bin/clickhouse
/build/obj-x86_64-linux-gnu/../src/Common/ThreadPool.cpp:199
/build/obj-x86_64-linux-gnu/../src/Common/ThreadPool.h:155
/usr/include/c++/9/bits/atomic_base.h:551
/usr/lib/debug/usr/bin/clickhouse
/lib/x86_64-linux-gnu/libpthread-2.27.so
/build/glibc-OTsEL5/glibc-2.27/misc/../sysdeps/unix/sysv/linux/x86_64/clone.S:97
addressToLineWithInlines
类似于 addressToLine，但返回包含所有内联函数的数组。因此，它比 addressToLine 慢。
注意
如果您使用的是官方 ClickHouse 包，则需要安装 clickhouse-common-static-dbg 包。
语法
addressToLineWithInlines(address_of_binary_instruction)
参数
address_of_binary_instruction(UInt64) — 正在运行的进程中指令的地址。
返回值
- 一个数组，其第一个元素是源代码文件名和文件中以冒号分隔的行号。从第二个元素开始，列出了内联函数的源代码文件名、行号和函数名称。如果函数找不到调试信息，则返回一个只有一个元素等于二进制文件名称的数组，否则如果地址无效，则返回一个空数组。 Array(String)。
示例
启用内省函数
SET allow_introspection_functions=1;
将函数应用于地址。
SELECT addressToLineWithInlines(531055181::UInt64);
┌─addressToLineWithInlines(CAST('531055181', 'UInt64'))────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│ ['./src/Functions/addressToLineWithInlines.cpp:98','./build_normal_debug/./src/Functions/addressToLineWithInlines.cpp:176:DB::(anonymous namespace)::FunctionAddressToLineWithInlines::implCached(unsigned long) const'] │
└──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
将函数应用于整个堆栈跟踪
SELECT
ta, addressToLineWithInlines(arrayJoin(trace) as ta)
FROM system.trace_log
WHERE
query_id = '5e173544-2020-45de-b645-5deebe2aae54';
arrayJoin 函数将数组拆分为行。
┌────────ta─┬─addressToLineWithInlines(arrayJoin(trace))───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│ 365497529 │ ['./build_normal_debug/./contrib/libcxx/include/string_view:252'] │
│ 365593602 │ ['./build_normal_debug/./src/Common/Dwarf.cpp:191'] │
│ 365593866 │ ['./build_normal_debug/./src/Common/Dwarf.cpp:0'] │
│ 365592528 │ ['./build_normal_debug/./src/Common/Dwarf.cpp:0'] │
│ 365591003 │ ['./build_normal_debug/./src/Common/Dwarf.cpp:477'] │
│ 365590479 │ ['./build_normal_debug/./src/Common/Dwarf.cpp:442'] │
│ 365590600 │ ['./build_normal_debug/./src/Common/Dwarf.cpp:457'] │
│ 365598941 │ ['./build_normal_debug/./src/Common/Dwarf.cpp:0'] │
│ 365607098 │ ['./build_normal_debug/./src/Common/Dwarf.cpp:0'] │
│ 365590571 │ ['./build_normal_debug/./src/Common/Dwarf.cpp:451'] │
│ 365598941 │ ['./build_normal_debug/./src/Common/Dwarf.cpp:0'] │
│ 365607098 │ ['./build_normal_debug/./src/Common/Dwarf.cpp:0'] │
│ 365590571 │ ['./build_normal_debug/./src/Common/Dwarf.cpp:451'] │
│ 365598941 │ ['./build_normal_debug/./src/Common/Dwarf.cpp:0'] │
│ 365607098 │ ['./build_normal_debug/./src/Common/Dwarf.cpp:0'] │
│ 365590571 │ ['./build_normal_debug/./src/Common/Dwarf.cpp:451'] │
│ 365598941 │ ['./build_normal_debug/./src/Common/Dwarf.cpp:0'] │
│ 365597289 │ ['./build_normal_debug/./src/Common/Dwarf.cpp:807'] │
│ 365599840 │ ['./build_normal_debug/./src/Common/Dwarf.cpp:1118'] │
│ 531058145 │ ['./build_normal_debug/./src/Functions/addressToLineWithInlines.cpp:152'] │
│ 531055181 │ ['./src/Functions/addressToLineWithInlines.cpp:98','./build_normal_debug/./src/Functions/addressToLineWithInlines.cpp:176:DB::(anonymous namespace)::FunctionAddressToLineWithInlines::implCached(unsigned long) const'] │
│ 422333613 │ ['./build_normal_debug/./src/Functions/IFunctionAdaptors.h:21'] │
│ 586866022 │ ['./build_normal_debug/./src/Functions/IFunction.cpp:216'] │
│ 586869053 │ ['./build_normal_debug/./src/Functions/IFunction.cpp:264'] │
│ 586873237 │ ['./build_normal_debug/./src/Functions/IFunction.cpp:334'] │
│ 597901620 │ ['./build_normal_debug/./src/Interpreters/ExpressionActions.cpp:601'] │
│ 597898534 │ ['./build_normal_debug/./src/Interpreters/ExpressionActions.cpp:718'] │
│ 630442912 │ ['./build_normal_debug/./src/Processors/Transforms/ExpressionTransform.cpp:23'] │
│ 546354050 │ ['./build_normal_debug/./src/Processors/ISimpleTransform.h:38'] │
│ 626026993 │ ['./build_normal_debug/./src/Processors/ISimpleTransform.cpp:89'] │
│ 626294022 │ ['./build_normal_debug/./src/Processors/Executors/ExecutionThreadContext.cpp:45'] │
│ 626293730 │ ['./build_normal_debug/./src/Processors/Executors/ExecutionThreadContext.cpp:63'] │
│ 626169525 │ ['./build_normal_debug/./src/Processors/Executors/PipelineExecutor.cpp:213'] │
│ 626170308 │ ['./build_normal_debug/./src/Processors/Executors/PipelineExecutor.cpp:178'] │
│ 626166348 │ ['./build_normal_debug/./src/Processors/Executors/PipelineExecutor.cpp:329'] │
│ 626163461 │ ['./build_normal_debug/./src/Processors/Executors/PipelineExecutor.cpp:84'] │
│ 626323536 │ ['./build_normal_debug/./src/Processors/Executors/PullingAsyncPipelineExecutor.cpp:85'] │
│ 626323277 │ ['./build_normal_debug/./src/Processors/Executors/PullingAsyncPipelineExecutor.cpp:112'] │
│ 626323133 │ ['./build_normal_debug/./contrib/libcxx/include/type_traits:3682'] │
│ 626323041 │ ['./build_normal_debug/./contrib/libcxx/include/tuple:1415'] │
└───────────┴──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
addressToSymbol
将 ClickHouse 服务器进程内的虚拟内存地址转换为 ClickHouse 对象文件中的符号。
语法
addressToSymbol(address_of_binary_instruction)
参数
address_of_binary_instruction(UInt64) — 正在运行的进程中指令的地址。
返回值
示例
启用内省函数
SET allow_introspection_functions=1;
从 trace_log 系统表中选择第一个字符串
SELECT * FROM system.trace_log LIMIT 1 \G;
Row 1:
──────
event_date: 2019-11-20
event_time: 2019-11-20 16:57:59
revision: 54429
timer_type: Real
thread_number: 48
query_id: 724028bf-f550-45aa-910d-2af6212b94ac
trace: [94138803686098,94138815010911,94138815096522,94138815101224,94138815102091,94138814222988,94138806823642,94138814457211,94138806823642,94138814457211,94138806823642,94138806795179,94138806796144,94138753770094,94138753771646,94138753760572,94138852407232,140399185266395,140399178045583]
trace 字段包含采样时堆栈跟踪。
获取单个地址的符号
SELECT addressToSymbol(94138803686098) \G;
Row 1:
──────
addressToSymbol(94138803686098): _ZNK2DB24IAggregateFunctionHelperINS_20AggregateFunctionSumImmNS_24AggregateFunctionSumDataImEEEEE19addBatchSinglePlaceEmPcPPKNS_7IColumnEPNS_5ArenaE
将函数应用于整个堆栈跟踪
SELECT
arrayStringConcat(arrayMap(x -> addressToSymbol(x), trace), '\n') AS trace_symbols
FROM system.trace_log
LIMIT 1
\G
arrayMap 函数允许使用 addressToSymbols 函数处理 trace 数组的每个元素。您可以在输出的 trace_symbols 列中看到此处理的结果。
Row 1:
──────
trace_symbols: _ZNK2DB24IAggregateFunctionHelperINS_20AggregateFunctionSumImmNS_24AggregateFunctionSumDataImEEEEE19addBatchSinglePlaceEmPcPPKNS_7IColumnEPNS_5ArenaE
_ZNK2DB10Aggregator21executeWithoutKeyImplERPcmPNS0_28AggregateFunctionInstructionEPNS_5ArenaE
_ZN2DB10Aggregator14executeOnBlockESt6vectorIN3COWINS_7IColumnEE13immutable_ptrIS3_EESaIS6_EEmRNS_22AggregatedDataVariantsERS1_IPKS3_SaISC_EERS1_ISE_SaISE_EERb
_ZN2DB10Aggregator14executeOnBlockERKNS_5BlockERNS_22AggregatedDataVariantsERSt6vectorIPKNS_7IColumnESaIS9_EERS6_ISB_SaISB_EERb
_ZN2DB10Aggregator7executeERKSt10shared_ptrINS_17IBlockInputStreamEERNS_22AggregatedDataVariantsE
_ZN2DB27AggregatingBlockInputStream8readImplEv
_ZN2DB17IBlockInputStream4readEv
_ZN2DB26ExpressionBlockInputStream8readImplEv
_ZN2DB17IBlockInputStream4readEv
_ZN2DB26ExpressionBlockInputStream8readImplEv
_ZN2DB17IBlockInputStream4readEv
_ZN2DB28AsynchronousBlockInputStream9calculateEv
_ZNSt17_Function_handlerIFvvEZN2DB28AsynchronousBlockInputStream4nextEvEUlvE_E9_M_invokeERKSt9_Any_data
_ZN14ThreadPoolImplI20ThreadFromGlobalPoolE6workerESt14_List_iteratorIS0_E
_ZZN20ThreadFromGlobalPoolC4IZN14ThreadPoolImplIS_E12scheduleImplIvEET_St8functionIFvvEEiSt8optionalImEEUlvE1_JEEEOS4_DpOT0_ENKUlvE_clEv
_ZN14ThreadPoolImplISt6threadE6workerESt14_List_iteratorIS0_E
execute_native_thread_routine
start_thread
clone
demangle
将您可以使用 addressToSymbol 函数获取的符号转换为 C++ 函数名称。
语法
demangle(symbol)
参数
symbol(String) — 来自对象文件的符号。
返回值
- C++ 函数的名称，或者如果符号无效则为空字符串。 String。
示例
启用内省函数
SET allow_introspection_functions=1;
从 trace_log 系统表中选择第一个字符串
SELECT * FROM system.trace_log LIMIT 1 \G;
Row 1:
──────
event_date: 2019-11-20
event_time: 2019-11-20 16:57:59
revision: 54429
timer_type: Real
thread_number: 48
query_id: 724028bf-f550-45aa-910d-2af6212b94ac
trace: [94138803686098,94138815010911,94138815096522,94138815101224,94138815102091,94138814222988,94138806823642,94138814457211,94138806823642,94138814457211,94138806823642,94138806795179,94138806796144,94138753770094,94138753771646,94138753760572,94138852407232,140399185266395,140399178045583]
trace 字段包含采样时堆栈跟踪。
获取单个地址的函数名称
SELECT demangle(addressToSymbol(94138803686098)) \G;
Row 1:
──────
demangle(addressToSymbol(94138803686098)): DB::IAggregateFunctionHelper<DB::AggregateFunctionSum<unsigned long, unsigned long, DB::AggregateFunctionSumData<unsigned long> > >::addBatchSinglePlace(unsigned long, char*, DB::IColumn const**, DB::Arena*) const
将函数应用于整个堆栈跟踪
SELECT
arrayStringConcat(arrayMap(x -> demangle(addressToSymbol(x)), trace), '\n') AS trace_functions
FROM system.trace_log
LIMIT 1
\G
arrayMap 函数允许使用 demangle 函数处理 trace 数组的每个元素。您可以在输出的 trace_functions 列中看到此处理的结果。
Row 1:
──────
trace_functions: DB::IAggregateFunctionHelper<DB::AggregateFunctionSum<unsigned long, unsigned long, DB::AggregateFunctionSumData<unsigned long> > >::addBatchSinglePlace(unsigned long, char*, DB::IColumn const**, DB::Arena*) const
DB::Aggregator::executeWithoutKeyImpl(char*&, unsigned long, DB::Aggregator::AggregateFunctionInstruction*, DB::Arena*) const
DB::Aggregator::executeOnBlock(std::vector<COW<DB::IColumn>::immutable_ptr<DB::IColumn>, std::allocator<COW<DB::IColumn>::immutable_ptr<DB::IColumn> > >, unsigned long, DB::AggregatedDataVariants&, std::vector<DB::IColumn const*, std::allocator<DB::IColumn const*> >&, std::vector<std::vector<DB::IColumn const*, std::allocator<DB::IColumn const*> >, std::allocator<std::vector<DB::IColumn const*, std::allocator<DB::IColumn const*> > > >&, bool&)
DB::Aggregator::executeOnBlock(DB::Block const&, DB::AggregatedDataVariants&, std::vector<DB::IColumn const*, std::allocator<DB::IColumn const*> >&, std::vector<std::vector<DB::IColumn const*, std::allocator<DB::IColumn const*> >, std::allocator<std::vector<DB::IColumn const*, std::allocator<DB::IColumn const*> > > >&, bool&)
DB::Aggregator::execute(std::shared_ptr<DB::IBlockInputStream> const&, DB::AggregatedDataVariants&)
DB::AggregatingBlockInputStream::readImpl()
DB::IBlockInputStream::read()
DB::ExpressionBlockInputStream::readImpl()
DB::IBlockInputStream::read()
DB::ExpressionBlockInputStream::readImpl()
DB::IBlockInputStream::read()
DB::AsynchronousBlockInputStream::calculate()
std::_Function_handler<void (), DB::AsynchronousBlockInputStream::next()::{lambda()#1}>::_M_invoke(std::_Any_data const&)
ThreadPoolImpl<ThreadFromGlobalPool>::worker(std::_List_iterator<ThreadFromGlobalPool>)
ThreadFromGlobalPool::ThreadFromGlobalPool<ThreadPoolImpl<ThreadFromGlobalPool>::scheduleImpl<void>(std::function<void ()>, int, std::optional<unsigned long>)::{lambda()#3}>(ThreadPoolImpl<ThreadFromGlobalPool>::scheduleImpl<void>(std::function<void ()>, int, std::optional<unsigned long>)::{lambda()#3}&&)::{lambda()#1}::operator()() const
ThreadPoolImpl<std::thread>::worker(std::_List_iterator<std::thread>)
execute_native_thread_routine
start_thread
clone
tid
返回当前 Block 所在的线程 ID。
语法
tid()
返回值
- 当前线程 ID。 Uint64。
示例
查询
SELECT tid();
结果
┌─tid()─┐
│ 3878 │
└───────┘
logTrace
为每个 Block 将跟踪日志消息发送到服务器日志。
语法
logTrace('message')
参数
message— 发送到服务器日志的消息。 String。
返回值
- 始终返回 0。
示例
查询
SELECT logTrace('logTrace message');
结果
┌─logTrace('logTrace message')─┐
│ 0 │
└──────────────────────────────┘