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'
ISSUES-1725: The result of union stmt whose child is outer join stmt is incorrect.
Example:
sql: (select k1 from empty) union all (select b.k1 k1 from left_table a left join empty b on a.k2 = b.k2);
context: the empty table has no data.
error result: 0
expect result: null
Reason:
The judgment (columns k1 who belongs to union tuple is nullable ) is incorrect.
It could not be determined by slot attribute of children when the slot is produced by the outer join.
The slot A is not nullable while the result of outer join is nullable which is same as slot A.
So, the judgment needs to consider if the slot is come from the outer join.
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.
