Currently, there are many profiles using add child profile to orgnanize profile into blocks. But it is wrong. Child profile will have a total time counter. Actually, what we should use is just a label.
- MemoryUsage:
- HashTable: 23.98 KB
- SerializeKeyArena: 446.75 KB
Add a new macro ADD_LABEL_COUNTER to add just a label in the profile.
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Co-authored-by: yiguolei <yiguolei@gmail.com>
Refactoring the filtering conditions in the current ExecNode from an expression tree to an array can simplify the process of adding runtime filters. It eliminates the need for complex merge operations and removes the requirement for the frontend to combine expressions into a single entity.
By representing the filtering conditions as an array, each condition can be treated individually, making it easier to add runtime filters without the need for complex merging logic. The array can store the individual conditions, and the runtime filter logic can iterate through the array to apply the filters as needed.
This refactoring simplifies the codebase, improves readability, and reduces the complexity associated with handling filtering conditions and adding runtime filters. It separates the conditions into discrete entities, enabling more straightforward manipulation and management within the execution node.
After the query check process memory exceed limit in Allocator, it will wait up to 5s.
Before, Allocator will not check whether the query is canceled while waiting for memory, this causes the query to not end quickly.
TabletSink and LoadChannel in BE are M: N relationship,
Every once in a while LoadChannel will randomly return its own runtime profile to a TabletSink, so usually all LoadChannel runtime profiles are saved on each TabletSink, and the timeliness of the same LoadChannel profile saved on different TabletSinks is different, and each TabletSink will periodically send fe reports all the LoadChannel profiles saved by itself, and ensures to update the latest LoadChannel profile according to the timestamp.
disallow call new method explicitly
force to use create_shared or create_unique to use shared ptr
placement new is allowed
reference https://abseil.io/tips/42 to add factory method to all class.
I think we should follow this guide because if throw exception in new method, the program will terminate.
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Co-authored-by: yiguolei <yiguolei@gmail.com>
Currently, there are some useless includes in the codebase. We can use a tool named include-what-you-use to optimize these includes. By using a strict include-what-you-use policy, we can get lots of benefits from it.
No check mem tracker limit and no cancel task in mem hook, only in Allocator. This helps in clearer analysis of memory issues and reduces performance loss.
PODArray/hash table/arena memory allocation will use Allocator.
Optimize mem limit exceeded log printing
Optimize compilation time
Currently, it takes too much time to build BE from source in workflow environments (P0/P1) which affects the efficiency of daily development.
We can measure the time by executing the following command.
time EXTRA_CXX_FLAGS='-O3' BUILD_TYPE=ASAN ./build.sh --be --fe --clean -j "$(nproc)"
This PR optimizes the compilation time by exploiting the following methods.
Reduce the codegen by removing some useless std::visit.
Disable the optimization for some template functions which are instantiated by std::visit conditionally (except for the RELEASE build).
mem tracker can be logically divided into 4 layers: 1)process 2)type 3)query/load/compation task etc. 4)exec node etc.
type includes
enum Type {
GLOBAL = 0, // Life cycle is the same as the process, e.g. Cache and default Orphan
QUERY = 1, // Count the memory consumption of all Query tasks.
LOAD = 2, // Count the memory consumption of all Load tasks.
COMPACTION = 3, // Count the memory consumption of all Base and Cumulative tasks.
SCHEMA_CHANGE = 4, // Count the memory consumption of all SchemaChange tasks.
CLONE = 5, // Count the memory consumption of all EngineCloneTask. Note: Memory that does not contain make/release snapshots.
BATCHLOAD = 6, // Count the memory consumption of all EngineBatchLoadTask.
CONSISTENCY = 7 // Count the memory consumption of all EngineChecksumTask.
}
Object pointers are no longer saved between each layer, and the values of process and each type are periodically aggregated.
other fix:
In [fix](memtracker) Fix transmit_tracker null pointer because phamp is not thread safe #13528, I tried to separate the memory that was manually abandoned in the query from the orphan mem tracker. But in the actual test, the accuracy of this part of the memory cannot be guaranteed, so put it back to the orphan mem tracker again.
