After all LRU Cache inherits from LRUCachePolicy, this will allow prune stale entry, eviction when memory exceeds limit, and define common properties. LRUCache constructor change to private, only allow LRUCachePolicy to construct it.
Impl DummyLRUCache, when LRU Cache capacity is 0, will no longer be meaningless insert and evict.
Manually track query/load/compaction/etc. memory in Allocator instead of mem hook.
Can still use Mem Hook when cannot manually track memory code segments and find memory locations during debugging.
This will cause memory tracking loss for Query, loss less than 10% compared to the past, but this is expected to be more controllable.
Similarly, Mem Hook will no longer track unowned memory to the orphan mem tracker by default, so the total memory of all MemTrackers will be less than before.
Not need to get memory size from jemalloc in Mem Hook each memory alloc and free, which would lose performance in the past.
Not require caching bthread local in pthread local for memory hook, in the past this has caused core dumps inside bthread, seems to be a bug in bthread.
ThreadContext life cycle to manual control
In the past, ThreadContext was automatically created when it was used for the first time (this was usually in the Jemalloc Hook when the first malloc memory), and was automatically destroyed when the thread exited.
Now instead of manually controlling the create and destroy of ThreadContext, it is mainly created manually when the task thread start and destroyed before the task thread end.
Run 43 clickbench query tests.
Use MemHook in the past:
In mow, primary key cache have a big impact on load performance, so we add a new cache type to seperate
it from page cache to make it more flexible in some cases
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.
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.
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.
Previously, bthread_getspecific was called every time bthread local was used. In the test at #10823, it was found that frequent calls to bthread_getspecific had performance problems.
So a cache is implemented on pthread local based on the btls key, but the btls key cannot correctly sense bthread switching.
So, based on bthread_self to get the bthread id to implement the cache.
The mem hook consumes the orphan tracker by default. If the thread does not attach other trackers, by default all consumption will be passed to the process tracker through the orphan tracker.
In real time, consumption of all other trackers + orphan tracker consumption = process tracker consumption.
Ideally, all threads are expected to attach to the specified tracker, so that "all memory has its own ownership", and the consumption of the orphan mem tracker is close to 0, but greater than 0.
Refactor TaggableLogger
Refactor status handling in agent task:
Unify log format in TaskWorkerPool
Pass Status to the top caller, and replace some OLAPInternalError with more detailed error message Status
Premature return with the opposite condition to reduce indention
1. solved the previous delayed unit test file size is too large (1.7G+) and the unit test link time is too long problem problems
2. Unify all unit tests into one file to significantly reduce unit test execution time to less than 3 mins
3. temporarily disable stream_load_test.cpp, metrics_action_test.cpp, load_channel_mgr_test.cpp because it will re-implement part of the code and affect other tests