Dayue Gao 8aa2cbe12d Load Rowset only once in a thread-safe manner (#2022) ...

[Storage]
This PR implements thread-safe `Rowset::load()` for both AlphaRowset and BetaRowset. The main changes are 

1. Introduce `DorisCallOnce<ReturnType>` to be the replacement for `DorisInitOnce` . It works for both Status and OLAPStatus.
2. `segment_v2::ColumnReader::init()` is now implemented by DorisCallOnce.
3. `segment_v2::Segment` is now created by a factory open() method. This guarantees all Segment instances are in opened state.
4. `segment_v2::Segment::_load_index()` is now implemented by DorisCallOnce.
5. Implement thread-safe load() for AlphaRowset and BetaRowset

2019-10-21 16:05:12 +08:00

..

agent

Refactor Storage Engine (#1478)

2019-07-15 21:18:22 +08:00

common

Uniform Status (#1317)

2019-06-14 23:38:31 +08:00

env

Use Env function to operate directory (#1980)

2019-10-15 09:25:12 +08:00

exec

Limit the memory usage of Loading process (#1954)

2019-10-15 09:26:20 +08:00

exprs

Make HLL be able to handle invalid data (#1908)

2019-09-29 10:55:23 +08:00

geo

Add spatial func (#1213)

2019-05-31 14:23:09 +08:00

http

Uniform Status (#1317)

2019-06-14 23:38:31 +08:00

olap

Load Rowset only once in a thread-safe manner (#2022)

2019-10-21 16:05:12 +08:00

runtime

Modify fixed partition feature (#1989)

2019-10-16 16:03:46 +08:00

udf

Change variable and namespace name in BE (#268)

2018-11-02 10:22:32 +08:00

util

Replace Arena with MemPool (#2012)

2019-10-19 15:53:24 +08:00