static async Task ReceiveMessages(string connectionString, int numPartitions, int numClients, bool verbose)
{
Console.WriteLine($"Receiving messages from {numPartitions} partitions using {numClients} client instances");
var clients = new EventHubClient[numClients];
for (var i = 0; i < numClients; i++)
{
clients[i] = new EventHubClient(connectionString, _eventHubName);
}
try
{
var client = clients.First();
var partitionIds = (await client.GetPartitionIdsAsync()).Take(numPartitions);
var partitions = await Task.WhenAll(partitionIds.Select(id => client.GetPartitionPropertiesAsync(id)));
var totalCount = (long)0;
foreach (var partition in partitions)
{
var begin = partition.BeginningSequenceNumber;
var end = partition.LastEnqueuedSequenceNumber;
var count = end - begin + 1;
totalCount += count;
if (verbose)
{
Console.WriteLine($"Partition: {partition.Id}, Begin: {begin}, End: {end}, Count: {count}");
}
}
if (verbose)
{
Console.WriteLine($"Total Count: {totalCount}");
}
var consumers = new EventHubConsumer[numPartitions];
for (var i = 0; i < numPartitions; i++)
{
consumers[i] = clients[i % numClients].CreateConsumer(EventHubConsumer.DefaultConsumerGroupName, partitions[i].Id, EventPosition.Earliest);
}
try
{
var receiveTasks = new Task <(int messagesReceived, long lastSequenceNumber)> [numPartitions];
var sw = Stopwatch.StartNew();
for (var i = 0; i < numPartitions; i++)
{
receiveTasks[i] = ReceiveAllMessages(consumers[i], partitions[i]);
}
var results = await Task.WhenAll(receiveTasks);
sw.Stop();
var elapsed = sw.Elapsed.TotalSeconds;
var messagesReceived = results.Select(r => r.messagesReceived).Sum();
var messagesPerSecond = messagesReceived / elapsed;
var megabytesPerSecond = (messagesPerSecond * _bytesPerMessage) / (1024 * 1024);
Console.WriteLine($"Received {messagesReceived} messages of size {_bytesPerMessage} in {elapsed:N2}s " +
$"({messagesPerSecond:N2} msg/s, {megabytesPerSecond:N2} MB/s)");
}
