ClickHouse/docs/zh/sql-reference/functions/introspection.md
Steve-金勇 5fc67379ea
Update introspection.md
Improve translation of Chinese. 
There are several language parts that hard to understand.
优化一些翻译,主要是语句不通的地方。
2020-12-10 16:36:05 +08:00

311 lines
11 KiB
Markdown
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

---
machine_translated: true
machine_translated_rev: 72537a2d527c63c07aa5d2361a8829f3895cf2bd
toc_priority: 65
toc_title: "\u81EA\u7701"
---
# 内省功能 {#introspection-functions}
您可以使用本章中描述的函数来反省 [ELF](https://en.wikipedia.org/wiki/Executable_and_Linkable_Format) 和 [DWARF](https://en.wikipedia.org/wiki/DWARF) 用于查询分析。
!!! warning "警告"
这些功能很慢,可能会强加安全考虑。
对于内省功能的正确操作:
- 安装 `clickhouse-common-static-dbg` 包。
- 设置 [allow_introspection_functions](../../operations/settings/settings.md#settings-allow_introspection_functions) 设置为1。
出于安全考虑,内省函数默认是关闭的。
ClickHouse将探查器报告保存到 [trace_log](../../operations/system-tables/trace_log.md#system_tables-trace_log) 系统表. 确保正确配置了表和探查器。
## addressToLine {#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。
如果您使用官方的ClickHouse软件包您需要安装 `clickhouse-common-static-dbg` 包。
**语法**
``` sql
addressToLine(address_of_binary_instruction)
```
**参数**
- `address_of_binary_instruction` ([UInt64](../../sql-reference/data-types/int-uint.md)) — 正在运行进程的指令地址。
**返回值**
- 源代码文件名和行号(用冒号分隔的行号)
示例, `/build/obj-x86_64-linux-gnu/../src/Common/ThreadPool.cpp:199`, where `199` is a line number.
- 如果函数找不到调试信息,返回二进制文件的名称。
- 如果地址无效,返回空字符串。
类型: [字符串](../../sql-reference/data-types/string.md).
**示例**
启用内省功能:
``` sql
SET allow_introspection_functions=1
```
从中选择第一个字符串 `trace_log` 系统表:
``` sql
SELECT * FROM system.trace_log LIMIT 1 \G
```
``` text
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` 字段包含采样时的堆栈跟踪。
获取单个地址的源代码文件名和行号:
``` sql
SELECT addressToLine(94784076370703) \G
```
``` text
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:
``` sql
SELECT
arrayStringConcat(arrayMap(x -> addressToLine(x), trace), '\n') AS trace_source_code_lines
FROM system.trace_log
LIMIT 1
\G
```
该 [arrayMap](higher-order-functions.md#higher_order_functions-array-map) 功能允许处理的每个单独的元素 `trace` 阵列由 `addressToLine` 功能。 这种处理的结果,你在看 `trace_source_code_lines` 列的输出。
``` text
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
```
## addressToSymbol {#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**
``` sql
addressToSymbol(address_of_binary_instruction)
```
**参数**
- `address_of_binary_instruction` ([UInt64](../../sql-reference/data-types/int-uint.md)) — Address of instruction in a running process.
**返回值**
- 来自ClickHouse对象文件的符号。
- 如果地址无效,返回空字符串。
类型: [字符串](../../sql-reference/data-types/string.md).
**示例**
启用内省功能:
``` sql
SET allow_introspection_functions=1
```
从中选择第一个字符串 `trace_log` 系统表:
``` sql
SELECT * FROM system.trace_log LIMIT 1 \G
```
``` text
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` 字段包含采样时的堆栈跟踪。
获取单个地址的符号:
``` sql
SELECT addressToSymbol(94138803686098) \G
```
``` text
Row 1:
──────
addressToSymbol(94138803686098): _ZNK2DB24IAggregateFunctionHelperINS_20AggregateFunctionSumImmNS_24AggregateFunctionSumDataImEEEEE19addBatchSinglePlaceEmPcPPKNS_7IColumnEPNS_5ArenaE
```
将函数应用于整个堆栈跟踪:
``` sql
SELECT
arrayStringConcat(arrayMap(x -> addressToSymbol(x), trace), '\n') AS trace_symbols
FROM system.trace_log
LIMIT 1
\G
```
该 [arrayMap](higher-order-functions.md#higher_order_functions-array-map) 功能允许处理的每个单独的元素 `trace` 阵列由 `addressToSymbols` 功能。 这种处理的结果,你在看 `trace_symbols` 列的输出。
``` text
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 {#demangle}
转换一个符号,您可以使用 [addressToSymbol](#addresstosymbol) 函数到C++函数名。
**语法**
``` sql
demangle(symbol)
```
**参数**
- `symbol` ([字符串](../../sql-reference/data-types/string.md)) — Symbol from an object file.
**返回值**
- C++函数的名称。
- 如果符号无效,则为空字符串。
类型: [字符串](../../sql-reference/data-types/string.md).
**示例**
启用内省功能:
``` sql
SET allow_introspection_functions=1
```
从中选择第一个字符串 `trace_log` 系统表:
``` sql
SELECT * FROM system.trace_log LIMIT 1 \G
```
``` text
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` 字段包含采样时的堆栈跟踪。
获取单个地址的函数名称:
``` sql
SELECT demangle(addressToSymbol(94138803686098)) \G
```
``` text
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:
``` sql
SELECT
arrayStringConcat(arrayMap(x -> demangle(addressToSymbol(x)), trace), '\n') AS trace_functions
FROM system.trace_log
LIMIT 1
\G
```
该 [arrayMap](higher-order-functions.md#higher_order_functions-array-map) 功能允许处理的每个单独的元素 `trace` 阵列由 `demangle` 功能。 这种处理的结果,你在看 `trace_functions` 列的输出。
``` text
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
```