Try to remove Connection tracking of iptables on both host and guest machines. Also try to look at the "sysctl -a |grep tcp" output to see if it's optimized or you have too many opened connections in the kernel connections table. else then network everything works fine? Eliezer On 6/6/2013 10:59 AM, linuxsupport wrote: > No one experienced such issue? > > > On Mon, Jun 3, 2013 at 4:41 PM, linuxsupport <lin.support at gmail.com> wrote: > >> Hi All, >> >> I am using CentOS 6.4 on 4 servers, guests are also CentOS 6.4 >> >> Network is setup using virtio, and vhost, this works well but sometime I >> see connection issue from application to DB. >> >> I found that sometimes latency increases from 0.200 ms approx to 123ms or >> even more sometimes, this happens only for 1-2 packets but keep happening >> after sometime. >> >> CPU load remains under 1, CPU usages is around 20-30%. >> >> If I ping from host machine to host machine then there is consistent >> latency, this only happens when ping from a guest machine to either other >> guest machines or a host machine. >> >> Did anyone face similar issue? >> > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos >