CavalliumDBEngine/src/main/java/io/net5/buffer/api/pool/MetricUtils.java
2022-03-16 13:47:56 +01:00

47 lines
1.3 KiB
Java

package io.netty5.buffer.api.pool;
import java.lang.invoke.MethodHandle;
import java.lang.invoke.MethodHandles;
import java.lang.invoke.MethodType;
import java.util.List;
/**
* Netty5 hides some metrics. This utility class can read them.
*/
public class MetricUtils {
private static final MethodHandle GET_ARENA_METRICS;
static {
var lookup = MethodHandles.lookup();
// Get the method handle that returns the metrics of each pool arena
MethodHandle handle = null;
try {
// Find the class
var pooledBufferClass = Class.forName("io.netty5.buffer.api.pool.PooledBufferAllocatorMetric");
// Find the handle of the method
handle = lookup.findVirtual(pooledBufferClass, "arenaMetrics", MethodType.methodType(List.class));
} catch (NoSuchMethodException | IllegalAccessException | ClassNotFoundException ignored) {
}
GET_ARENA_METRICS = handle;
}
/**
* Get the metrics of each pool arena of a pooled allocator
* @param allocator Pooled allocator
* @return A list of {@link PoolArenaMetric}
*/
@SuppressWarnings("unchecked")
public static List<PoolArenaMetric> getPoolArenaMetrics(PooledBufferAllocator allocator) {
var metric = allocator.metric();
try {
// Invoke the method to get the metrics
return (List<PoolArenaMetric>) GET_ARENA_METRICS.invoke(metric);
} catch (Throwable e) {
return List.of();
}
}
}