JedisPool getResource block in multi-thread

[lonnyzhang423]

Here is my pool config

GenericObjectPoolConfig config = new GenericObjectPoolConfig();
config.setMaxTotal(8);
config.setMaxIdle(8);
config.setMinIdle(0);
config.setBlockWhenExhausted(true);
config.setMaxWaitMillis(-1);
jedisPool = new JedisPool(config, "localhost", 6379);

My test code

ExecutorService service = Executors.newCachedThreadPool();
service.submit(() -> {
    while (true) {
        int active = jedisPool.getNumActive();
        int idle = jedisPool.getNumIdle();
        int waiters = jedisPool.getNumWaiters();
        System.out.println(String.format("[PoolMonitor] active:%s idle:%s waiters:%s", active, idle, waiters));
        ThreadUtil.sleepSilently(1000);
    }
});
AtomicLong l = new AtomicLong(0);
for (int i = 0; i < 10; i++) {
    service.submit(() -> {
        try {
            while (true) {
                try (Jedis jedis =jedisPool.getResource()) {//BLOCK HERE
                    System.out.println("count:" + l.incrementAndGet());
                    jedis.get("abc");
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    });
}

Test result

count:5161
count:5162
count:5163
count:5164
count:5165
count:5166
count:5167
count:5168
count:5169
[PoolMonitor] active:8 idle:0 waiters:10
[PoolMonitor] active:8 idle:0 waiters:10
[PoolMonitor] active:8 idle:0 waiters:10
[PoolMonitor] active:8 idle:0 waiters:10

Why jedisPool.getResource() block and never return?

[sazzad16]

@lonnyzhang423 Put a positive value in setMaxWaitMillis.

[lonnyzhang423]

@sazzad16 Thanks for your reply. But as for me,I need to block forever when the pool exhausted. I wonder why jedis instance stay active and not be returned to the pool since pool is thread safe and get("abc") will not block for long time?

[bubbajoe]

Having this problem also, how do we free the resources?

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