Poor man's profiler on query level #4247
Conversation
| throw Exception("The only argument for function " + getName() + " must be array of UInt64. Found " | ||
| + arguments[0].type->getName() + " instead.", ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT); | ||
|
|
||
| return std::make_shared<DataTypeString>(); |
There was a problem hiding this comment.
If it takes array of addresses - let it return array of strings.
There was a problem hiding this comment.
Because otherwise it will be difficult to aggregate.
There was a problem hiding this comment.
Even better: let it be a function that will symbolize a single address.
And we will apply it with arrayMap.
| @@ -41,6 +42,8 @@ void ThreadStatus::attachQueryContext(Context & query_context_) | |||
| if (!thread_group->global_context) | |||
| thread_group->global_context = global_context; | |||
| } | |||
|
|
|||
| initQueryProfiler(); | |||
There was a problem hiding this comment.
It will probably set up query profiler only in first query execution thread.
Look at my recent changes related to setpriority in this file.
|
|
||
| using TimerDataType = TraceLogElement::TimerDataType; | ||
|
|
||
| const TimerDataType::Values TraceLogElement::timer_values = { |
| columns[i++]->insert(event_time); | ||
| columns[i++]->insert(static_cast<UInt8>(timer_type)); | ||
| columns[i++]->insertData(query_id.data(), query_id.size()); | ||
| columns[i++]->insert(trace); |
There was a problem hiding this comment.
Let's also add server version info (as in query_log) - because it's crucial for symbolizing traces.
There was a problem hiding this comment.
And
String thread_name;
UInt32 thread_number{};
Int32 os_thread_id{};
UInt32 master_thread_number{};
Int32 master_os_thread_id{};
as in query_thread_log.
libs/libcommon/src/Sleep.cpp
Outdated
|
|
||
| finish_time.tv_sec += (nanoseconds / resolution) + extra_second; | ||
|
|
||
| while (clock_nanosleep(clock_type, TIMER_ABSTIME, &finish_time, nullptr) == EINTR); |
There was a problem hiding this comment.
Please put semicolon on a new line :)
|
TODO:
|
laplab
changed the title
I hereby agree to the terms of the CLA available at: https://yandex.ru/legal/cla/?lang=en
Category: New Feature
Short description: Poor man's profiler for each query being executed
Detailed description:
Poor man's profiler stops a program at random time points to collect current backtrace. After some time a developer can analyze which code points profiler visits most often. Such places probably have some efficiency issues and could be optimized during the performance analysis.
Original: https://poormansprofiler.org
Technically we give each query-related thread a timer and setup signal listener which collects information required for backtrace and passes it to the pipe. Separate thread (
TraceCollector) reads information from the pipe and writes it to system tablesystem.trace_log.ToDo
TraceCollectorgracefully (current version is killed by the OS after clickhouse server stops)