先给大家一段代码示例：
@AutowiredRedisson redisson;@GetMapping("/modifyInfo/{id}")public Result modifyInfo(@PathVariable String id) {String lockKey = RedisLockConstant.ERP_CLUE_LOCK + id;RLock rLock = redisson.getLock(lockKey);try {rLock.tryLock(15,10, TimeUnit.SECONDS);doSomething(id);} catch (InterruptedException e) {log.error("加锁失败",e);return Result.error("网络拥堵请稍后再试", null);} finally {rLock.unlock();}return Result.success();}private void doSomething(String id) {log.info("业务请求- start -- {},{}",id,Thread.currentThread().getName());try {Thread.sleep(6000);} catch (InterruptedException e) {throw new RuntimeException(e);}log.info("业务请求-end - {},{}",id,Thread.currentThread().getName());}
问题点分析：
rLock.tryLock(15,10, TimeUnit.SECONDS);
先说tryLock三个参数的含义：
接着分析：
rLock.tryLock(100,10, TimeUnit.SECONDS);
设置等待时间100S ,如果6个请求同时过来了，看起来没问题，日志显示排队执行的。
2024-12-16 17:34:28.868 INFO [TID: N/A] http-nio-9115-exec-2 com.alpha.erp.controller.accounts.SupplierAccountsController - 业务请求- start -- 11,http-nio-9115-exec-2
2024-12-16 17:34:34.868 INFO [TID: N/A] http-nio-9115-exec-2 com.alpha.erp.controller.accounts.SupplierAccountsController - 业务请求-end - 11,http-nio-9115-exec-2
2024-12-16 17:34:34.880 INFO [TID: N/A] http-nio-9115-exec-1 com.alpha.erp.controller.accounts.SupplierAccountsController - 业务请求- start -- 11,http-nio-9115-exec-1
2024-12-16 17:34:40.881 INFO [TID: N/A] http-nio-9115-exec-1 com.alpha.erp.controller.accounts.SupplierAccountsController - 业务请求-end - 11,http-nio-9115-exec-1
2024-12-16 17:34:40.890 INFO [TID: N/A] http-nio-9115-exec-9 com.alpha.erp.controller.accounts.SupplierAccountsController - 业务请求- start -- 11,http-nio-9115-exec-9
2024-12-16 17:34:46.891 INFO [TID: N/A] http-nio-9115-exec-9 com.alpha.erp.controller.accounts.SupplierAccountsController - 业务请求-end - 11,http-nio-9115-exec-9
2024-12-16 17:34:46.905 INFO [TID: N/A] http-nio-9115-exec-3 com.alpha.erp.controller.accounts.SupplierAccountsController - 业务请求- start -- 11,http-nio-9115-exec-3
2024-12-16 17:34:52.905 INFO [TID: N/A] http-nio-9115-exec-3 com.alpha.erp.controller.accounts.SupplierAccountsController - 业务请求-end - 11,http-nio-9115-exec-3
2024-12-16 17:34:52.910 INFO [TID: N/A] http-nio-9115-exec-6 com.alpha.erp.controller.accounts.SupplierAccountsController - 业务请求- start -- 11,http-nio-9115-exec-6
2024-12-16 17:34:58.910 INFO [TID: N/A] http-nio-9115-exec-6 com.alpha.erp.controller.accounts.SupplierAccountsController - 业务请求-end - 11,http-nio-9115-exec-6
2024-12-16 17:34:58.927 INFO [TID: N/A] http-nio-9115-exec-4 com.alpha.erp.controller.accounts.SupplierAccountsController - 业务请求- start -- 11,http-nio-9115-exec-4
2024-12-16 17:35:04.928 INFO [TID: N/A] http-nio-9115-exec-4 com.alpha.erp.controller.accounts.SupplierAccountsController - 业务请求-end - 11,http-nio-9115-exec-4
可以理解为，每个线程都是进来最大等待100S，执行过程中，每个线程都没超过最大时间，都很文明的在等待；
如果我们把最大等待时间调整后继续测试，还是6个请求：
rLock.tryLock(15,10, TimeUnit.SECONDS);
上面有三个请求已经超过最大等待时间了，3个请求排队了，另外3个最大时间已过，15S后，这3个一起不文明的进来了。同时还出现了锁的释放也乱了，出现了异常；
总结：可以理解为，最大等待时间就是并发的每个线程，最大的文明时间。如果阻塞的请求过多，排队执行的时间累加起来超过最大等待时间，那继续排队的那些线程就开始不文明了。同时涌入，也就是不可控了
