Summary:
This is similar to https://github.com/facebook/rocksdb/issues/9862, including the following fixes/refactoring:
1. If OPTIONS file is specified via `-options_file`, majority of options will be loaded from the file. We should not
overwrite options that have been loaded from the file. Instead, we configure only fields of options which are
shared objects and not set by the OPTIONS file. We also configure a few fields, e.g. `create_if_missing` necessary
for stress test to run.
2. Refactor options initialization into three functions, `InitializeOptionsFromFile()`, `InitializeOptionsFromFlags()`
and `InitializeOptionsGeneral()` similar to db_bench. I hope they can be shared in the future. The high-level logic is
as follows:
```cpp
if (!InitializeOptionsFromFile(...)) {
InitializeOptionsFromFlags(...);
}
InitializeOptionsGeneral(...);
```
3. Currently, the setting for `block_cache_compressed` does not seem correct because it by default specifies a
size of `numeric_limits<size_t>::max()` ((size_t)-1). According to code comments, `-1` indicates default value,
which should be referring to `num_shard_bits` argument.
4. Clarify `fail_if_options_file_error`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9943
Test Plan:
1. make check
2. Run stress tests, and manually check generated OPTIONS file and compare them with input OPTIONS files
Reviewed By: jay-zhuang
Differential Revision: D36133769
Pulled By: riversand963
fbshipit-source-id: 35dacdc090a0a72c922907170cd132b9ecaa073e