* Add `raft.snapshot.method` in configuration file to control the method of applying snapshots
  - "block" decode snapshot data as a block
  - "file1" decode snapshot data as DTFiles (directory mode) [**By default**]
* Add a stream `SSTFilesToBlockInputStream` to decode snapshot data into blocks
* Add a stream `BoundedSSTFilesToBlockInputStream` to bound the blocks read from SSTFilesToBlockInputStream by column `_tidb_rowid`
* Add a stream `SSTFilesToDTFilesOutputStream` that accept `BoundedSSTFilesToBlockInputStream` as input stream to write blocks into DTFiles
* Make `STORAGE_FORMAT_CURRENT` to be `STORAGE_FORMAT_V2` by default to support ingest DTFile into DT engine
* Fix the bug that the block decoded from SSTFile is not sorted by primary key and version (#1888)
* Fix panic with feature compaction filter with DTFile
* Fix ingest write amplification after snapshot apply optimization (#1913)

Co-authored-by: Zhigao Tong <tongzhigao@pingcap.com>
Signed-off-by: JaySon-Huang <jayson.hjs@gmail.com>

Signed-off-by: ti-srebot <ti-srebot@pingcap.com>

Co-authored-by: Flowyi <flowbehappy@gmail.com>

cherry pick pingcap#1821 to release-5.0 (pingcap#1827)

Signed-off-by: ti-srebot <ti-srebot@pingcap.com>

Co-authored-by: xufei <xufei@pingcap.com>

Remove ReplicatedMergeTree family (pingcap#1805) (pingcap#1826)

cherry pick pingcap#1835 to release-5.0 (pingcap#1840)

Signed-off-by: ti-srebot <ti-srebot@pingcap.com>

Co-authored-by: xufei <xufei@pingcap.com>

Use file path as cache key (pingcap#1852) (pingcap#1862)

Lazily initializing DeltaMergeStore  (pingcap#1423) (pingcap#1751) (pingcap#1868)

Add background gc check thread for DeltaTree storage (pingcap#1742) (pingcap#1828)

* cherry pick pingcap#1742 to release-5.0

Signed-off-by: ti-srebot <ti-srebot@pingcap.com>

* fix conflict

Co-authored-by: lidezhu <47731263+lidezhu@users.noreply.github.com>

Fix calculate stable property (pingcap#1839) (pingcap#1878)

* cherry pick pingcap#1839 to release-5.0

Signed-off-by: ti-srebot <ti-srebot@pingcap.com>

* fix compile and cherry pick a small fix

Co-authored-by: lidezhu <47731263+lidezhu@users.noreply.github.com>

Fix client-c mistake setting current_ts to 0 when resolving lock for async commit (pingcap#1856) (pingcap#1870)

support constant folding in dbg coprocessor (pingcap#1881) (pingcap#1884)

Optimize & Reduce time cost about ci test (pingcap#1849) (pingcap#1894)

* reduce time cost about ci test by parallel
* add `-DNO_WERROR=ON` to cmake config for release-darwin build
* Fix tidb_ghpr_tics_test fail (pingcap#1895)

Signed-off-by: Zhigao Tong <tongzhigao@pingcap.com>

Fix panic with feature `compaction filter` in release-5.0 (pingcap#1891)

Init store in background task. (pingcap#1843,pingcap#1896) (pingcap#1874)

Push down filter on timestamp type column to storage layer (pingcap#1875) (pingcap#1906)

* cherry pick pingcap#1875 to release-5.0

Signed-off-by: ti-srebot <ti-srebot@pingcap.com>

* remove irrevalant code

Co-authored-by: lidezhu <47731263+lidezhu@users.noreply.github.com>

Fix ExchangeSender: remove duplicated write stream operation (pingcap#1379) (pingcap#1883)

cherry pick pingcap#1917 to release-5.0 (pingcap#1923)

Signed-off-by: ti-srebot <ti-srebot@pingcap.com>

Co-authored-by: Fu Zhe <fuzhe1989@gmail.com>

Pre-handle SSTFiles to DTFiles when applying snapshots (pingcap#1439) (pingcap#1867)

* Add `raft.snapshot.method` in configuration file to control the method of applying snapshots
  - "block" decode snapshot data as a block
  - "file1" decode snapshot data as DTFiles (directory mode) [**By default**]
* Add a stream `SSTFilesToBlockInputStream` to decode snapshot data into blocks
* Add a stream `BoundedSSTFilesToBlockInputStream` to bound the blocks read from SSTFilesToBlockInputStream by column `_tidb_rowid`
* Add a stream `SSTFilesToDTFilesOutputStream` that accept `BoundedSSTFilesToBlockInputStream` as input stream to write blocks into DTFiles
* Make `STORAGE_FORMAT_CURRENT` to be `STORAGE_FORMAT_V2` by default to support ingest DTFile into DT engine
* Fix the bug that the block decoded from SSTFile is not sorted by primary key and version (pingcap#1888)
* Fix panic with feature compaction filter with DTFile
* Fix ingest write amplification after snapshot apply optimization (pingcap#1913)

Co-authored-by: Zhigao Tong <tongzhigao@pingcap.com>
Signed-off-by: JaySon-Huang <jayson.hjs@gmail.com>

Cast int/real as real (pingcap#1911) (pingcap#1928)

Fix the problem that old dmfile is not removed atomically (pingcap#1918) (pingcap#1925)

Eliminate the table lock between reading,writing and DDL operators for TiFlash (pingcap#1736) (pingcap#1858)

* Eliminate the table lock between reading,writing and DDL operators for TiFlash (pingcap#1736)

1. Port the latest `RWLock` for `IStorage` from Clickhouse. "phase-fair rwlocks have been shown to provide more predictable timings compared to task-fair rwlocks for certain workloads (for relatively low share of writes, <25%). Brandenburg B, Anderson J, (2010)"
2. Refactor the lock model for `IStorage` to eliminate the lock between reading, writing, and DDL operations.
3. Acquire table lock by QueryID/threadName instead of function name
4. Tombstone the database after receiving a "drop" DDL from TiDB. Physically drop the databases / tables after gc safe point.
5. Remove some outdated tests under `tests/mutable-test/txn_schema` (all those tests are ported into `tests/delta-merge-test/raft/schema`)

* Mark FIXME for conflict codes
Conflicts:
  dbms/src/Flash/Coprocessor/DAGQueryBlockInterpreter.cpp

Signed-off-by: JaySon-Huang <jayson.hjs@gmail.com>

cached tics code incase of clone same code repeatedly (pingcap#1994) (pingcap#2001)

Add row & bytes threshold config for CompactLog (pingcap#1997) (pingcap#2005)

* cherry pick pingcap#1997 to release-5.0

Signed-off-by: ti-srebot <ti-srebot@pingcap.com>
Co-authored-by: Zhigao Tong <tongzhigao@pingcap.com>

Fix the bug that incomplete write batches are not truncated (pingcap#1934) (pingcap#2003)

Revert "Push down filter on timestamp type column to storage layer (pingcap#1875) (pingcap#1906)" (pingcap#2010)

This reverts commit 630b612.

Revert Lazily Init Store (pingcap#2011)

* Revert "Init store in background task. (pingcap#1843,pingcap#1896) (pingcap#1874)"

This reverts commit 0882461.

Conflicts:
	dbms/src/Storages/StorageDeltaMerge.cpp

* format code

* Revert "Lazily initializing DeltaMergeStore  (pingcap#1423) (pingcap#1751) (pingcap#1868)"

This reverts commit bbce050.

Conflicts:
	dbms/src/Storages/DeltaMerge/tests/gtest_dm_storage_delta_merge.cpp
	dbms/src/Storages/StorageDeltaMerge.cpp
	dbms/src/Storages/StorageDeltaMerge.h

Co-authored-by: JinheLin <linjinhe@pingcap.com>
Co-authored-by: Flowyi <flowbehappy@gmail.com>

Revert "background gc thread" (pingcap#2015)

* Revert "Fix calculate stable property (pingcap#1839) (pingcap#1878)"

This reverts commit 6a9eb58.

* Revert "Add background gc check thread for DeltaTree storage (pingcap#1742) (pingcap#1828)"

This reverts commit cbbbd09.

* remove code

* format code

* format code

* fix test compile

* fix comment

Fix the potential concurrency problem when clone the shared delta index (pingcap#2030) (pingcap#2033)

* cherry pick pingcap#2030 to release-5.0

Signed-off-by: ti-srebot <ti-srebot@pingcap.com>

* Update dbms/src/Storages/DeltaMerge/DeltaIndex.h

Co-authored-by: JaySon <jayson.hjs@gmail.com>

Co-authored-by: lidezhu <47731263+lidezhu@users.noreply.github.com>
Co-authored-by: JaySon <jayson.hjs@gmail.com>

Fix bug for unexpected deleted ingest file (pingcap#2047) (pingcap#2048)

* Only enable GC for DTFiles after they get applied to all segments.
* Refine some loggings

Signed-off-by: JaySon-Huang <jayson.hjs@gmail.com>

Fix cast int as time (pingcap#1788) (pingcap#1893)

cherry pick pingcap#1903 to release-5.0 (pingcap#1915)

Signed-off-by: ti-srebot <ti-srebot@pingcap.com>

Fix ingesting file may add ref page to deleted page (pingcap#2054) (pingcap#2055)

1. Put the ingest file id into `storage_pool.data` before ingesting them into segments
2. Add ref pages to the ingest files for each segment
3. Delete the original page id after all

Signed-off-by: JaySon-Huang <jayson.hjs@gmail.com>

Fix compile error on Mac Clang 12.0.5 (pingcap#2058) (pingcap#2070)

cherry pick pingcap#2017 pingcap#2020 pingcap#2051 to release-5.0 (pingcap#2074)

Revert "cherry pick pingcap#2017 pingcap#2020 pingcap#2051 to release-5.0 (pingcap#2074)"

This reverts commit 8e0712c.

Revert "Fix compile error on Mac Clang 12.0.5 (pingcap#2058) (pingcap#2070)"

This reverts commit 3c31b92.

Revert "Fix ingesting file may add ref page to deleted page (pingcap#2054) (pingcap#2055)"

This reverts commit c773d61.

Revert "Fix bug for unexpected deleted ingest file (pingcap#2047) (pingcap#2048)"

This reverts commit b329618.

Revert "Pre-handle SSTFiles to DTFiles when applying snapshots (pingcap#1439) (pingcap#1867)"

This reverts commit c947fd6.

 Conflicts:
	dbms/src/Common/FailPoint.cpp
	dbms/src/Storages/DeltaMerge/File/DMFileBlockOutputStream.h
	dbms/src/Storages/DeltaMerge/File/DMFileWriter.h
	dbms/src/Storages/DeltaMerge/ReorganizeBlockInputStream.h
	dbms/src/Storages/DeltaMerge/SSTFilesToBlockInputStream.cpp
	dbms/src/Storages/DeltaMerge/SSTFilesToBlockInputStream.h
	dbms/src/Storages/DeltaMerge/SSTFilesToDTFilesOutputStream.cpp
	dbms/src/Storages/DeltaMerge/Segment.cpp
	dbms/src/Storages/DeltaMerge/StableValueSpace.cpp
	dbms/src/Storages/DeltaMerge/tests/gtest_dm_file.cpp
	dbms/src/Storages/DeltaMerge/tests/gtest_dm_storage_delta_merge.cpp
	dbms/src/Storages/StorageDeltaMerge.cpp
	dbms/src/Storages/StorageDeltaMerge.h
	dbms/src/Storages/Transaction/ApplySnapshot.cpp
	dbms/src/Storages/Transaction/PartitionStreams.cpp
	tests/delta-merge-test/raft/schema/drop_on_restart.test

Fix comment

Signed-off-by: JaySon-Huang <jayson.hjs@gmail.com>