AWS Redis : JedisConnectionException: java.net.SocketException: Too many open files - amazon-web-services

Question

I have configured redis using AWS Elasticache and connecting it through tomcat installed on AWS EC2.
Following is my code:
private JedisPool jedisPool = null;
#PostConstruct
private void initialiseJedisPools() {
try {
String redisHost = RESOURCES.getProperty("redis.master.host");
if(Objects.nonNull(redisHost)) {
Integer redisPort = Integer.valueOf(RESOURCES.getProperty("redis.master.port"));
jedisPool = new JedisPool(redisHost, redisPort);
}
} catch (NumberFormatException exception) {
logger.error("Exception occurred while initialising jedis pool.", exception);
}
}
public void addKey(String key, String value, Integer secondsToExpire) {
if (Objects.nonNull(jedisPool)) {
try (Jedis jedis = jedisPool.getResource()) {
jedis.set(key, value);
if (Objects.nonNull(secondsToExpire)) {
jedis.expire(key, secondsToExpire.intValue());
}
} catch (JedisException jedisException) {
logger.error("Exception thrown while adding key in cache.", jedisException);
}
}
}
Often a while I get the following error and I have to restart tomcat to make it work.
redis.clients.jedis.exceptions.JedisConnectionException: Could not get a resource from the pool
at redis.clients.util.Pool.getResource(Pool.java:53)
at redis.clients.jedis.JedisPool.getResource(JedisPool.java:226)
.
.
.
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
Caused by: redis.clients.jedis.exceptions.JedisConnectionException: java.net.SocketException: Too many open files
at redis.clients.jedis.Connection.connect(Connection.java:207)
at redis.clients.jedis.BinaryClient.connect(BinaryClient.java:93)
at redis.clients.jedis.BinaryJedis.connect(BinaryJedis.java:1767)
at redis.clients.jedis.JedisFactory.makeObject(JedisFactory.java:106)
at org.apache.commons.pool2.impl.GenericObjectPool.create(GenericObjectPool.java:868)
at org.apache.commons.pool2.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:435)
at org.apache.commons.pool2.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:363)
at redis.clients.util.Pool.getResource(Pool.java:49)
... 10 more
Caused by: java.net.SocketException: Too many open files
at java.net.Socket.createImpl(Socket.java:460)
at java.net.Socket.getImpl(Socket.java:520)
at java.net.Socket.setReuseAddress(Socket.java:1449)
at redis.clients.jedis.Connection.connect(Connection.java:174)
... 17 more
I have tried increasing the ulimit for open files, configuring a JedisPoolConfig for maxTotal, maxIdle, minIdle, etc, but no success.
Please suggest.

Answer 1

We have also faced similar issue in past for jedis connection with error "java.net.SocketException: Too many open files"
This happens due to jedis connection not getting closed.
call jedisPool.returnResourse(jedis) or jedis.close()