ZSTD compression is fast with high compression ratio. It can be used to archive higher compression ratio
than default Lz4f codec for storing cost sensitive data such as logs.
Compared to Lz4f codec, we see zstd codec get 35% compressed size off, 30% faster at first time read without OS page
cache, 40% slower at second time read with OS page cache in the following comparison test.
test data: 25GB text log, 110 million rows
test table: test_table(ts varchar(30), log string)
test SQL: set enable_vectorized_engine=1; select sum(length(log)) from test_table
be.conf: disable_storage_page_cache = true
set this config to disable doris page cache to avoid all data cached in memory for test real decompression speed.
test result
master branch with lz4f codec result:
- compressed size 4.3G
- SQL first exec time(read data from disk + decompress + little computation) : 18.3s
- SQL second exec time(read data from OS pagecache + decompress + little computation) : 2.4s
this branch with zstd codec (hardcode enable it) result:
- compressed size: 2.8G
- SQL first exec time: 12.8s
- SQL second exec time: 3.4s
1. Fix Lru Cache MemTracker consumption value is negative.
2. Fix compaction Cache MemTracker has no track.
3. Add USE_MEM_TRACKER compile option.
4. Make sure the malloc/free hook is not stopped at any time.
* [Enhancement][Vectorized]build hash table with new thread, as non-vectorized past do
edit after comments
* format code with clang format
Co-authored-by: lidongyang <dongyang.li@rateup.com.cn>
Co-authored-by: stephen <hello-stephen@qq.com>
Currently, the libhdfs3 library integrated by doris BE does not support accessing the cluster with kerberos authentication
enabled, and found that kerberos-related dependencies(gsasl and krb5) were not added when build libhdfs3.
so, this pr will enable kerberos support and rebuild libhdfs3 with dependencies gsasl and krb5:
- gsasl version: 1.8.0
- krb5 version: 1.19
* [Refactor][Bug-Fix][Load Vec] Refactor code of basescanner and vjson/vparquet/vbroker scanner
1. fix bug of vjson scanner not support `range_from_file_path`
2. fix bug of vjson/vbrocker scanner core dump by src/dest slot nullable is different
3. fix bug of vparquest filter_block reference of column in not 1
4. refactor code to simple all the code
It only changed vectorized load, not original row based load.
Co-authored-by: lihaopeng <lihaopeng@baidu.com>
Hive and trino/presto would automatically trim the trailing spaces but Doris doesn't.
This would cause different query result with hive.
Add a new session variable "trim_tailing_spaces_for_external_table_query".
If set to true, when reading csv from broker scan node, it will trim the tailing space of the column