Configuration Best Practices
If you are running on Linux, consider these best practices. Typical Linux defaults are not necessarily well tuned for the needs of an IO intensive application like NiFi. For all of these areas, your distribution's requirements may vary. Use these sections as advice, but consult your distribution-specific documentation for how best to achieve these recommendations.
- Maximum File Handles
NiFi will at any one time potentially have a very large number of file handles open. Increase the limits by editing '/etc/security/limits.conf' to add something like
* hard nofile 50000 * soft nofile 50000
- Maximum Forked Processes
NiFi may be configured to generate a significant number of threads. To increase the allowable number edit '/etc/security/limits.conf'
* hard nproc 10000 * soft nproc 10000
And your distribution may require an edit to /etc/security/limits.d/90-nproc.conf by adding
* soft nproc 10000
- Increase the number of TCP socket ports available
This is particularly important if your flow will be setting up and tearing down a large number of sockets in small period of time.
sudo sysctl -w net.ipv4.ip_local_port_range="10000 65000"
- Set how long sockets stay in a TIMED_WAIT state when closed
You don't want your sockets to sit and linger too long given that you want to be able to quickly setup and teardown new sockets. It is a good idea to read more about it but to adjust do something like
sudo sysctl -w net.ipv4.netfilter.ip_conntrack_tcp_timeout_time_wait="1"
- Tell Linux you never want NiFi to swap
Swapping is fantastic for some applications. It isn't good for something like NiFi that always wants to be running. To tell Linux you'd like swapping off you can edit '/etc/sysctl.conf' to add the following line
vm.swappiness = 0
For the partitions handling the various NiFi repos turn off things like 'atime'. Doing so can cause a surprising bump in throughput. Edit the '/etc/fstab' file and for the partition(s) of interest add the 'noatime' option.