private static int getTotalWaitingCommands() {
int totalWaitingCommands = 0;
final String hystrixPoolName = EXAMPLE_GROUP;
HystrixThreadPoolKey key = HystrixThreadPoolKey.Factory.asKey(hystrixPoolName);
HystrixThreadPoolMetrics metrics = HystrixThreadPoolMetrics.getInstance(key);
if (metrics != null) {
Number active = metrics.getCurrentActiveCount();
Number queueSize = metrics.getCurrentQueueSize();
totalWaitingCommands = active.intValue() + queueSize.intValue();
LOG.debug("{} has {} commands waiting", hystrixPoolName, totalWaitingCommands);
}
return totalWaitingCommands;
}
/**
* Get or create the {@link HystrixCommandMetrics} instance for a given {@link HystrixCommandKey}.
*
* <p>This is thread-safe and ensures only 1 {@link HystrixCommandMetrics} per {@link
* HystrixCommandKey}.
*
* @param key {@link HystrixCommandKey} of {@link HystrixCommand} instance requesting the {@link
* HystrixCommandMetrics}
* @param commandGroup Pass-thru to {@link HystrixCommandMetrics} instance on first time when
* constructed
* @param properties Pass-thru to {@link HystrixCommandMetrics} instance on first time when
* constructed
* @return {@link HystrixCommandMetrics}
*/
public static HystrixCommandMetrics getInstance(
HystrixCommandKey key,
HystrixCommandGroupKey commandGroup,
HystrixThreadPoolKey threadPoolKey,
HystrixCommandProperties properties) {
// attempt to retrieve from cache first
HystrixCommandMetrics commandMetrics = metrics.get(key.name());
if (commandMetrics != null) {
return commandMetrics;
}
// it doesn't exist so we need to create it
// now check to see if we need to create a synthetic threadPoolKey
HystrixThreadPoolKey nonNullThreadPoolKey;
if (threadPoolKey == null) {
nonNullThreadPoolKey = HystrixThreadPoolKey.Factory.asKey(commandGroup.name());
} else {
nonNullThreadPoolKey = threadPoolKey;
}
commandMetrics =
new HystrixCommandMetrics(
key,
commandGroup,
nonNullThreadPoolKey,
properties,
HystrixPlugins.getInstance().getEventNotifier());
// attempt to store it (race other threads)
HystrixCommandMetrics existing = metrics.putIfAbsent(key.name(), commandMetrics);
if (existing == null) {
// we won the thread-race to store the instance we created
return commandMetrics;
} else {
// we lost so return 'existing' and let the one we created be garbage collected
return existing;
}
}
