Summary:
## Overview
In this PR, we introduce support for setting the RocksDB native logger through Java. As mentioned in the discussion on the [Google Group discussion](https://groups.google.com/g/rocksdb/c/xYmbEs4sqRM/m/e73E4whJAQAJ), this work is primarily motivated by the JDK 17 [performance regression in JNI thread attach/detach calls](https://bugs.openjdk.org/browse/JDK-8314859): the only existing RocksJava logging configuration call, `setLogger`, invokes the provided logger over the JNI.
## Changes
Specifically, these changes add support for the `devnull` and `stderr` native loggers. For the `stderr` logger, we add the ability to prefix every log with a `logPrefix`, so that it becomes possible know which database a particular log is coming from (if multiple databases are in use). The API looks like the following:
```java
Options opts = new Options();
NativeLogger stderrNativeLogger = NativeLogger.newStderrLogger(
InfoLogLevel.DEBUG_LEVEL, "[my prefix here]");
options.setLogger(stderrNativeLogger);
try (final RocksDB db = RocksDB.open(options, ...)) {...}
// Cleanup
stderrNativeLogger.close()
opts.close();
```
Note that the API to set the logger is the same, via `Options::setLogger` (or `DBOptions::setLogger`). However, it will set the RocksDB logger to be native when the provided logger is an instance of `NativeLogger`.
## Testing
Two tests have been added in `NativeLoggerTest.java`. The first test creates both the `devnull` and `stderr` loggers, and sets them on the associated `Options`. However, to avoid polluting the testing output with logs from `stderr`, only the `devnull` logger is actually used in the test. The second test does the same logic, but for `DBOptions`.
It is possible to manually verify the `stderr` logger by modifying the tests slightly, and observing that the console indeed gets cluttered with logs from `stderr`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12213
Reviewed By: cbi42
Differential Revision: D52772306
Pulled By: ajkr
fbshipit-source-id: 4026895f78f9cc250daf6bfa57427957e2d8b053
Summary:
This should fix an import issue detected in meta internal tests.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10604
Test Plan: Unit Tests.
Reviewed By: hx235
Differential Revision: D39120414
Pulled By: gitbw95
fbshipit-source-id: dbd016d7f47b9f54aab5ea61e8d3cd79734f46af
