Add `MergeRangeFileReader` to merge small IO to optimize parquet&orc read performance.
`MergeRangeFileReader` is a FileReader that efficiently supports random access in format like parquet and orc.
In order to merge small IO in parquet and orc, the random access ranges should be generated when creating the
reader. The random access ranges is a list of ranges that order by offset.
The range in random access ranges should be reading sequentially, can be skipped, but can't be read repeatedly.
When calling read_at, if the start offset located in random access ranges, the slice size should not span two ranges.
For example, in parquet, the random access ranges is the column offsets in a row group.
When reading at offset, if [offset, offset + 8MB) contains many random access ranges,
the reader will read data in [offset, offset + 8MB) as a whole, and copy the data in random access ranges into small
buffers(name as box, default 1MB, 64MB in total). A box can be occupied by many ranges,
and use a reference counter to record how many ranges are cached in the box. If reference counter equals zero,
the box can be release or reused by other ranges. When there is no empty box for a new read operation,
the read operation will do directly.
## Effects
The runtime of ClickBench reduces from 102s to 77s, and the runtime of Query 24 reduces from 24.74s to 9.45s.
The profile of Query 24:
```
VFILE_SCAN_NODE (id=0):(Active: 8s344ms, % non-child: 83.06%)
- FileReadBytes: 534.46 MB
- FileReadCalls: 1.031K (1031)
- FileReadTime: 28s801ms
- GetNextTime: 8s304ms
- MaxScannerThreadNum: 12
- MergedSmallIO: 0ns
- CopyTime: 157.774ms
- MergedBytes: 549.91 MB
- MergedIO: 94
- ReadTime: 28s642ms
- RequestBytes: 507.96 MB
- RequestIO: 1.001K (1001)
- NumScanners: 18
```
1001 request IOs has been merged into 94 IOs.
## Remaining problems
1. Add p2 regression test in nest PR
2. Profiles are scattered in various codes and will be refactored in the next PR
3. Support ORC reader
after pr #18670
could use jvm parameters to init jdbc datasource,
but when set JDBC_MIN_POOL=0, it can be immediately closed.
There is no need to wait for the recycling timer.
* [bugfix](memleak) UserFunctionCache may have memory leak during close
* [bugfix](memleak) UserFunctionCache may have memory leak during close
---------
Co-authored-by: yiguolei <yiguolei@gmail.com>
* [bugfix](memoryleak) inlist is memory leak if the type is int
---------
Co-authored-by: yiguolei <yiguolei@gmail.com>
Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
Fix broker load p2 test case error.
1. Move test data from cos Hong kong region to Beijing region.
2. Move broker load test to p2 group.
3. Fix error message mismatch error.
* Add unexpected/result support
* Rename result.hpp -> result.h && Add NOLINT in expected.hpp
* Add NOLINT in result.h to avoid clang-tidy checker
* Rename result.h to expected.h
* Add Apache License for be/src/util/expected.hpp
* Disable clang-format in be util/expected.hpp
1. Supports sampling to collect statistics
2. Improved syntax for collecting statistics
3. Support histogram specifies the number of buckets
4. Tweaked some code structure
---
The syntax supports WITH and PROPERTIES, using the same syntax as before.
Column Statistics Collection Syntax:
```SQL
ANALYZE [ SYNC ] TABLE table_name
[ (column_name [, ...]) ]
[ [WITH SYNC] | [WITH INCREMENTAL] | [WITH SAMPLE PERCENT | ROWS ] ]
[ PROPERTIES ('key' = 'value', ...) ];
```
Column histogram collection syntax:
```SQL
ANALYZE [ SYNC ] TABLE table_name
[ (column_name [, ...]) ]
UPDATE HISTOGRAM
[ [ WITH SYNC ][ WITH INCREMENTAL ][ WITH SAMPLE PERCENT | ROWS ][ WITH BUCKETS ] ]
[ PROPERTIES ('key' = 'value', ...) ];
```
Illustrate:
- sync:Collect statistics synchronously. Return after collecting.
- incremental:Collect statistics incrementally. Incremental collection of histogram statistics is not supported.
- sample percent | rows:Collect statistics by sampling. Scale and number of rows can be sampled.
- buckets:Specifies the maximum number of buckets generated when collecting histogram statistics.
- table_name: The purpose table for collecting statistics. Can be of the form `db_name.table_name`.
- column_name: The specified destination column must be a column that exists in `table_name`, and multiple column names are separated by commas.
- properties:Properties used to set statistics tasks. Currently only the following configurations are supported (equivalent to the with statement)
- 'sync' = 'true'
- 'incremental' = 'true'
- 'sample.percent' = '50'
- 'sample.rows' = '1000'
- 'num.buckets' = 10
---
TODO:
- Supplement the complete p0 test
- `Incremental` statistics see #18653
add two phase read topn opt, the legacy planner's PR are:
- #15642
- #16460
- #16848
TODO:
we forbid limit(sort(project(scan))) since be core when plan has a project on the scan.
we need to remove this restirction after we fix be bug