kafka clear topic

Kafka is designed for the distributed environment, so if the log file can actually be understood as a message database, put in the same place, then will inevitably bring a decline in availability, a hang all, if the full amount of copies to all machines, then there is too much redundancy of data, and because each machine's disk size is limited , so even if there are more machines, the messages that can be processed are limited by the disk and cannot e

some time ago in the Kafka QQ Group was asked about this--about how Java consumer dynamically modify topic subscription issues. It's really a good question to think about it, because if you simply hold the consumer instance in another thread and then call subscribe to modify it, the consumer side will inevitably throw an exception Concurrentmodificationexception:kafkaconsumer is isn'tsafe for multi-threade

1. Use the command line method: [lch@linux129 bin]$./kafka-topics.sh--create--zookeeper hadoop221:2181,hadoop222:2181--replication-factor 2-- Partitions 2--topic test_ttt parameter description:--replication-factor: Indicates the number of copies, written here 2, indicating there will be two copies--partitions: indicates there will be two par Tition, shown in log logs, is two foldersThis is the test_ttt-0 an

;ImportKafka.admin.RackAwareMode;Importkafka.utils.ZkUtils; Public classKafkautil { Public Static voidcreatekafatopic (String zkstr,kafkatopicbean topic) {zkutils zkutils=zkutils. Apply (ZKSTR,30000, 30000, jaasutils.iszksecurityenabled ()); Adminutils.createtopic (Zkutils, Topic.gettopicname (), Topic.getpartition (), Topic.getreplication (), NewProperties (),Newrackawaremode.enforced$ ()); Zkutils.close (); } Public Static voiddeletekaf