Does Linux distribution influence network speed?

October 16, 2015 1.2k views
Linux Basics Deployment CentOS Debian

Hi guys,

Just find something interesting.
Today, when I use Centos5 x86, I did a network speed test by :
wget --no-check-certificate -O - -o /dev/null | bash
then get result for 4.5 mb/s from cachefly and other locations around 2-3 mb/s.

When I change to Centos6 x86 and Detian8 X86, doing the same thing , then result become 22 mb/s from cachefly and other locations around 5-8 mb/s. Just 5 times more.

Centos5 picture
Centos6 picutre
Debian8 picture

i didn't test on Ubuntu.

What's wrong here? Just curious... Is this a issue related to OS or just DO template problem or anything else?

My vps current in Singapore, all systems are tested serval times with clean install.

Any ideas?


  • Did you rebuild the existing droplet for each of these tests or did you create a fresh droplet for each? A fresh droplet would likely be located on a different physical hypervisor which would be under differing load. In any case you should be able to see better than 4-5mbps so i would recommend opening a ticket with our support team if you continue to see this so they can investigate further.

  • I didn't do a fresh install in another location, as I would like to keep my current IP, But I do test this several times by reinstalling from image.

1 Answer

I have solved this by edit /etc/sysctl.conf, with:

[root@centos5 ~]# sysctl -a  | grep mem
net.ipv4.udp_wmem_min = 4096
net.ipv4.udp_rmem_min = 4096
net.ipv4.udp_mem = 49056    65408   98112
net.ipv4.tcp_rmem = 10240   87380   12582912
net.ipv4.tcp_wmem = 10240   87380   12582912
net.ipv4.tcp_mem = 12288    16384   24576
net.ipv4.igmp_max_memberships = 20
net.core.optmem_max = 10240
net.core.rmem_default = 110592
net.core.wmem_default = 110592
net.core.rmem_max = 12582912
net.core.wmem_max = 12582912
vm.lowmem_reserve_ratio = 256   256 32
vm.overcommit_memory = 0

more information can be found here and here

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