Summary:
Replace dynamic_cast<> so that users can choose to build with RTTI off, so that they can save several bytes per object, and get tiny more memory available.
Some nontrivial changes:
1. Add Comparator::GetRootComparator() to get around the internal comparator hack
2. Add the two experiemental functions to DB
3. Add TableFactory::GetOptionString() to avoid unnecessary casting to get the option string
4. Since 3 is done, move the parsing option functions for table factory to table factory files too, to be symmetric.
Closes https://github.com/facebook/rocksdb/pull/2645
Differential Revision: D5502723
Pulled By: siying
fbshipit-source-id: fd13cec5601cf68a554d87bfcf056f2ffa5fbf7c
Summary:
Added a flag, `ignore_unknown_options`, to skip unknown options when loading an options file (using `LoadLatestOptions`/`LoadOptionsFromFile`) or while verifying options (using `CheckOptionsCompatibility`). This will help in downgrading the db to an older version.
Also added `--ignore_unknown_options` flag to ldb
**Example Use case:**
In MyRocks, if copying from newer version to older version, it is often impossible to start because of new RocksDB options that don't exist in older version, even though data format is compatible.
MyRocks uses these load and verify functions in [ha_rocksdb.cc::check_rocksdb_options_compatibility](e004fd9f41/storage/rocksdb/ha_rocksdb.cc (L3348-L3401)).
**Test Plan:**
Updated the unit tests.
`make check`
ldb:
$ ./ldb --db=/tmp/test_db --create_if_missing put a1 b1
OK
Now edit /tmp/test_db/<OPTIONS-file> and add an unknown option.
Try loading the options now, and it fails:
$ ./ldb --db=/tmp/test_db --try_load_options get a1
Failed: Invalid argument: Unrecognized option DBOptions:: abcd
Passes with the new --ignore_unknown_options flag
$ ./ldb --db=/tmp/test_db --try_load_options --ignore_unknown_options get a1
b1
Closes https://github.com/facebook/rocksdb/pull/2423
Differential Revision: D5212091
Pulled By: sagar0
fbshipit-source-id: 2ec17636feb47dc0351b53a77e5f15ef7cbf2ca7
Summary:
Move some files under util/ to new directories env/, monitoring/ options/ and cache/
Closes https://github.com/facebook/rocksdb/pull/2090
Differential Revision: D4833681
Pulled By: siying
fbshipit-source-id: 2fd8bef
