In Doris, one block has 1024 rows.
1. If the previous ScanKey scan rows multiple blocks,
and also the final block has 1024 rows just right.
2. The current ScanKey scan rows with number less than one block.
Under the two conditions, if not seek block, the position of prefix shortkey columns is wrong.
I add ChunkAllocator in this CL to put unused memory chunk to a chunk
pool other than return it to system allocator. Now we only change
MemPool's chunk allocation and free to this.
And two configuration are introduduced too. 'chunk_reserved_bytes_limit'
is the limit of how many bytes this chunk pool can reserve in total and
its default value is 2147483648(2GB). 'use_mmap_allocate_chunk': if
chunk is allocated via mmap and default value is false.
And in my test case with default configuration a simple like
"select * from table limit 10", this can improve throughput from 280 QPS
to to 650 QPS. And when I config 'chunk_reserved_bytes_limit' to 0,
which means this is disabled, the throughput is the same with origin's.
Commit kafka offset in routine load
Kafka will decide whether to delete data based on whether all consumer group is commit offset or not. If there is no commit offset, the kafka server disk may be full
1. Support specifying label to Insert Into stmt.
INSERT INTO tbl1 WITH LABEL label1 ...;
2. Return job' state corresponding to the existing label in result of stream load.
...
"Status": "Label Already Exists",
"ExistingJobStatus": "FINISHED"
...
3. Return the recent 2000 transactions in SHOW PROC '/transactions'
The new msg of limit exceed: "Memory exceed limit. %msg, Backend:%ip, fragment:%id Used:% , Limit:%. xxx".
This commit unifies the msg of 'Memory exceed limit' such as check_query_state, RETURN_IF_LIMIT_EXCEEDED and LIMIT_EXCEEDED.
Path Hash of a replica in metadata should be set immediately after replica is created.
And we should not depend on path hash to find replicas. Because path hash may be set
delayed.
