Hi Ming, Maybe this ticket could be useful to you: https://issues.apache.org/jira/browse/KAFKA-7504
Guozhang On Fri, Aug 28, 2020 at 8:21 AM Ming Liu <minga...@gmail.com> wrote: > Hi > One major reason that Kafka is fast is because it is using sendfile() > for zero copy, as what it described at > https://kafka.apache.org/documentation/#producerconfigs, > > This combination of pagecache and sendfile means that on a Kafka > cluster where the consumers are mostly caught up you will see no read > activity on the disks whatsoever as they will be serving data entirely > from cache. > > However, when I ran tracing on all my kafka brokers, I didn't get a > single sendfile system call, why his discrepancy? > > sudo ./syscount -p 126806 -d 30 > Tracing syscalls, printing top 10... Ctrl+C to quit. > [17:44:10] > SYSCALL COUNT > epoll_wait 108482 > write 107165 > epoll_ctl 95058 > futex 86716 > read 86388 > pread 26910 > fstat 9213 > getrusage 120 > close 27 > open 21 > -- -- Guozhang
