Just One Pure Coder
by leelight · Published · Updated
不明觉厉！线上部署Kafka和ES，为啥JVM堆内存分配越大，性能反而越低？
kafka、elasticsearch等系统，线上生产环境部署时，是依赖os cache来缓冲大量数据的。假如你有一台机器，32GB的内存，你如果在搞不清状况的情况下，傻傻的认为还是给JVM分配越大内存越好，比如给了16G的堆内存空间给JVM。那么这样分配下来，os cache剩下的内存，可能就不到10GB了，因为本身其他的程序还要占用几个GB的内存。
我的观点是：不建议用户使用 Kafka Streams，因为其缺少检查点机制，也不具备随机排序等功能，而 KSQL 以 Kafka Streams 为基础，因此其同样继承了后者所固有的不少问题。
Tags: Kafka
by leelight · Published February 24, 2019 · Last modified June 22, 2019
by leelight · Published January 4, 2019 · Last modified June 15, 2019
by leelight · Published December 19, 2018 · Last modified June 15, 2019
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