Operating System Checks

Before deploying Doris, complete the following operating system checks and configurations:

Check item	Purpose
Disable swap partition	Avoid kernel policies that affect performance
Disable Transparent Huge Pages (THP)	Prevent memory fragmentation and performance fluctuations
Increase virtual memory areas	Avoid running out of file handles
Disable CPU power-saving mode	Ensure stable performance under high load
Reset on network connection overflow	Avoid hanging connections under high concurrency
Open ports / disable firewall	Ensure communication between components
Increase the number of file handles	Support a large number of table data files
Install NTP service	Ensure metadata time accuracy < 5000ms

Disable Swap Partition

Disabling swap prevents the kernel from moving data to the swap partition, which would affect Doris performance.

Temporary disable (reverts after reboot):

swapoff -a

Permanent disable: comment out the swap line in /etc/fstab and reboot to take effect.

# /etc/fstab
# <file system>        <dir>         <type>    <options>             <dump> <pass>
tmpfs                  /tmp          tmpfs     nodev,nosuid          0      0
/dev/sda1              /             ext4      defaults,noatime      0      1
# /dev/sda2              none          swap      defaults              0      0
/dev/sda3              /home         ext4      defaults,noatime      0      2

Disable Transparent Huge Pages

Disabling THP (Transparent Huge Pages) reduces memory fragmentation and ensures that Doris uses memory stably.

Temporary disable:

echo madvise > /sys/kernel/mm/transparent_hugepage/enabled
echo madvise > /sys/kernel/mm/transparent_hugepage/defrag

Permanent disable:

cat >> /etc/rc.d/rc.local << EOF
   echo madvise > /sys/kernel/mm/transparent_hugepage/enabled
   echo madvise > /sys/kernel/mm/transparent_hugepage/defrag
EOF
chmod +x /etc/rc.d/rc.local

Increase Virtual Memory Areas

Increasing the VMA (virtual memory areas) prevents Doris from reporting Too many open files errors during startup or runtime.

cat >> /etc/sysctl.conf << EOF
vm.max_map_count = 2000000
EOF

sysctl -p

Disable CPU Power-Saving Mode

Disabling power-saving mode ensures stable CPU frequency under high load. If the CPU does not support Scaling Governor, you can skip this step.

echo 'performance' | sudo tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor

Reset on Network Connection Overflow

Enabling tcp_abort_on_overflow immediately aborts connections when overflow occurs, avoiding long-hanging connections under high load.

cat >> /etc/sysctl.conf << EOF
net.ipv4.tcp_abort_on_overflow=1
EOF

sysctl -p

Open Ports

If a port is unreachable, troubleshoot the firewall:

sudo systemctl stop firewalld.service
sudo systemctl disable firewalld.service

Or open the corresponding ports based on the Doris port configuration.

Increase File Handle Limits

Doris relies on a large number of files to manage table data, so the file handle limit needs to be raised.

vi /etc/security/limits.conf
* soft nofile 1000000
* hard nofile 1000000

The session must be restarted after the change takes effect.

Install NTP Service

Ensure that the clocks of all machines in the cluster are synchronized. The metadata time accuracy must be < 5000ms.

sudo systemctl start ntpd.service
sudo systemctl enable ntpd.service