the processes on this server do not involve io read operation. the code is developed by ourself. so I don't know where these io read come from. by the way, pidstat only show disk io ,not network io, is that right? | | yf chu | | 邮箱：cyflhn at 163.com | 签名由 网易邮箱大师 定制 On 03/05/2021 16:33, Simon Matter wrote: Hi, > We have experienced a very weird problem. The load of the server machine > is very high. We use "pidstat" and find that the disk read io is very > high. If disk read IO is very high, what does it read and what generates the reads? Simon > But the processes running on this server do not perform any disk read > operation. > We also noticed that when we execute "top" command, for most of processes, > the values in "SHR" column are zero. > Compared with other normal servers, we found that by executing "free -m", > the result shows that the buff/cache value in this server is lower than > the value of other normal servers. > We also found that there were lots of major page faults by executing "ps > -o majflt,minflt". > Swap is not enabled on this server. What could be the reason for this > issue? > > > The centos version:CentOS Linux release 7.3.1611 > kernel version:3.10.0-693.21.1.std7a.el7.0.x86_64 > _______________________________________________ > CentOS mailing list > CentOS at centos.org > https://lists.centos.org/mailman/listinfo/centos > _______________________________________________ CentOS mailing list CentOS at centos.org https://lists.centos.org/mailman/listinfo/centos