Tras habilitar la QPS throttling feature, las solicitudes que superen el umbral pueden devolver errores THROTTLED. Use los ejemplos a continuación de código para implementar una lógica de reintentos del lado del cliente.
Jedis
Este ejemplo usa la versión 5.2.0 de Jedis.
Parámetros de reintento
|
Parámetro |
Valor |
Descripción |
|
|
10 |
Número máximo de reintentos antes de lanzar la excepción |
|
Espera inicial |
2 s |
Tiempo de espera antes del primer reintento (2¹ segundos) |
|
Multiplicador de espera |
2x |
Cada reintento subsiguiente duplica la espera: 2 s, 4 s, 8 s, ... |
|
Error reintentado |
|
Solo se reintentan los errores |
Dependencia de Maven
<!-- This example uses version 5.2.0. -->
<dependency>
<groupId>redis.clients</groupId>
<artifactId>jedis</artifactId>
<version>5.2.0</version>
</dependency>
Ejemplo de código
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;
import redis.clients.jedis.JedisPoolConfig;
import redis.clients.jedis.exceptions.JedisException;
public class JedisThrottledTest {
private static final Logger logger = LoggerFactory.getLogger(JedisThrottledTest.class);
private static final int MAX_RETRY = 10; // Maximum retry attempts
public static void main(String[] args) {
if (args.length < 3) {
System.out.println("Usage: java -jar JedisThrottledTest.jar <host> <port> <password>");
return;
}
String host = args[0];
int port = Integer.parseInt(args[1]);
String password = args[2];
JedisPoolConfig poolConfig = new JedisPoolConfig();
poolConfig.setMaxTotal(32);
poolConfig.setMaxIdle(32);
poolConfig.setMinIdle(16);
JedisPool jedisPool = new JedisPool(poolConfig, host, port, 3000, password);
for (int i = 0; i < 4; i++) {
new Thread(new Runnable() {
@Override
public void run() {
for (int i = 0; i < Integer.MAX_VALUE; i++) {
executeWithRetry(jedisPool, "key" + i, "value" + i);
}
}
}).start();
}
}
private static void executeWithRetry(JedisPool jedisPool, String key, String value) {
int retryCount = 0;
while (retryCount < MAX_RETRY) {
try (Jedis jedis = jedisPool.getResource()) {
jedis.set(key, value);
break;
} catch (JedisException e) {
if (e.getMessage().contains("THROTTLED")) {
logger.info("Throttled error occurred (attempt " + retryCount + "): " + e.getMessage());
retryCount++;
if (retryCount >= MAX_RETRY) {
logger.info("Max retry attempts reached.");
throw e;
}
try {
int sleepTime = (int)Math.pow(2, retryCount);
Thread.sleep(sleepTime * 1000);
} catch (InterruptedException ie) {
Thread.currentThread().interrupt();
throw new RuntimeException("Thread interrupted during retry delay", ie);
}
} else {
throw e;
}
}
}
}
}
Valkey-java
Use la versión 5.4.0 o posterior de valkey-java.
Parámetros de reintento
|
Parámetro |
Valor |
Descripción |
|
|
100 |
Número máximo de reintentos |
|
|
1,000 s |
Tiempo total máximo dedicado a los reintentos |
|
Espera inicial |
1 s |
Tiempo de espera antes del primer reintento (2⁰ segundos) |
|
Multiplicador de espera |
2x |
Cada reintento subsiguiente duplica la espera: 1 s, 2 s, 4 s, ... |
|
Error reintentado |
|
Solo los mensajes que contienen |
Dependencia de Maven
<dependency>
<groupId>io.valkey</groupId>
<artifactId>valkey-java</artifactId>
<version>5.4.0</version>
</dependency>
Ejemplo de código
El componente ExceptionHandler en Valkey-java permite registrar devoluciones de llamada para patrones de error específicos. Este ejemplo registra una devolución de llamada de espera exponencial para errores THROTTLED, de modo que la lógica de reintentos queda separada del código de su aplicación.
import java.time.Duration;
import io.valkey.DefaultJedisClientConfig;
import io.valkey.ExceptionHandler;
import io.valkey.HostAndPort;
import io.valkey.UnifiedJedis;
import io.valkey.providers.PooledConnectionProvider;
import org.apache.commons.pool2.impl.GenericObjectPoolConfig;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class ThrottledTest {
private static final Logger logger = LoggerFactory.getLogger(ThrottledTest.class);
/**
* Implements exponential backoff.
*/
static class ExponentialBackoffCallback implements ExceptionHandler.ErrorCallback {
private int attempt = 0;
@Override
public void onError(String errorMessage) {
int sleepTime = (int)Math.pow(2, attempt);
try {
logger.info("Sleeping for " + sleepTime + " seconds before handling: " + errorMessage);
Thread.sleep(sleepTime * 1000);
} catch (InterruptedException ie) {
// Ignore the error.
}
attempt++;
}
}
public static void main(String[] args) {
if (args.length < 3) {
System.out.println("Usage: java -jar ThrottledTest.jar <host> <port> <password>");
return;
}
String host = args[0];
int port = Integer.parseInt(args[1]);
String password = args[2];
GenericObjectPoolConfig poolConfig = new GenericObjectPoolConfig();
poolConfig.setMaxTotal(32);
poolConfig.setMaxIdle(32);
poolConfig.setMinIdle(16);
int maxAttempts = 100; // Maximum retry attempts
Duration maxTotalRetriesDuration = Duration.ofSeconds(1000); // Maximum total duration for retries
PooledConnectionProvider provider = new PooledConnectionProvider(new HostAndPort(host, port),
DefaultJedisClientConfig.builder().password(password).build(), poolConfig);
ExceptionHandler handler = new ExceptionHandler();
handler.register(
message -> message.contains("THROTTLED"),
new ExponentialBackoffCallback()
);
UnifiedJedis unifiedJedis = new UnifiedJedis(provider, maxAttempts, maxTotalRetriesDuration, handler);
for (int i = 0; i < 4; i++) { // Use four threads to generate high QPS.
new Thread(new Runnable() {
@Override
public void run() {
for (int i = 0; i < Integer.MAX_VALUE; i++) {
try {
unifiedJedis.set("" + i, "" + i);
} catch (Exception e) {
logger.error("Error occurred {}", e.getMessage());
}
}
}
}).start();
}
}
}
redis-py
Este ejemplo usa la versión 6.1.1 de redis-py.
Parámetros de reintento
|
Parámetro |
Valor |
Descripción |
|
|
10 |
Número máximo de reintentos antes de generar la excepción |
|
Espera inicial |
2 s |
Tiempo de espera antes del primer reintento (2¹ segundos) |
|
Multiplicador de espera |
2x |
Cada reintento subsiguiente duplica la espera: 2 s, 4 s, 8 s, ... |
|
|
3 s |
Tiempo de espera de conexión |
|
Error reintentado |
|
Solo se reintentan los errores |
Ejemplo de código
import sys
import time
import threading
import logging
from redis import Redis, RedisError
logging.basicConfig(level=logging.INFO)
logger = logging.getLogger(__name__)
MAX_RETRY = 10 # Maximum retry attempts
def execute_with_retry(redis_client, key, value):
retry_count = 0
while retry_count < MAX_RETRY:
try:
redis_client.set(key, value)
break # If successful, exit the loop.
except RedisError as e:
if "THROTTLED" in str(e):
logger.info(f"Throttled error occurred (attempt {retry_count}): {e}")
retry_count += 1
if retry_count >= MAX_RETRY:
logger.info("Max retry attempts reached.")
raise e
sleep_time = 2 ** retry_count
time.sleep(sleep_time)
else:
logger.error(f"Non-throttled Redis error: {e}")
raise e
def worker(redis_client):
i = 0
while True:
try:
execute_with_retry(redis_client, f"key{i}", f"value{i}")
i += 1
except Exception as e:
logger.exception(f"Unexpected error in worker: {e}")
time.sleep(1) # Avoid tight loop in case of persistent errors
def main():
if len(sys.argv) < 4:
print("Usage: python script.py <host> <port> <password>")
return
host = sys.argv[1]
port = int(sys.argv[2])
password = sys.argv[3]
redis_client = Redis(
host=host,
port=port,
password=password,
socket_timeout=3,
decode_responses=True
)
# Test the connection.
try:
redis_client.ping()
logger.info("Successfully connected to Redis")
except RedisError as e:
logger.error(f"Failed to connect to Redis: {e}")
return
# Create and start 10 threads.
threads = []
for i in range(10):
thread = threading.Thread(target=worker, args=(redis_client,))
thread.daemon = True
thread.start()
threads.append(thread)
logger.info(f"Started worker thread {i}")
# Keep the main thread running.
try:
while True:
time.sleep(1)
except KeyboardInterrupt:
logger.info("Program interrupted. Exiting...")
# Wait for all threads to complete.
for thread in threads:
thread.join()
if __name__ == "__main__":
main()