Error: "Unable to lock JVM memory (ENOMEM)"

Upsource continuously shows "Indexing in progress" for some (all) revisions, or Apache Cassandra database gets restarted on a regular basis. Going through Upsource logs you encounter the following error:

Unable to lock JVM memory (ENOMEM). This can result in part of the JVM being swapped out, especially with mmapped I/O enabled. Increase RLIMIT_MEMLOCK or run Cassandra as root

or:

Too many open files..

Solution

Insufficient resource limits may result in this kind of error. To mitigate this we recommend setting:

maximum open files to 100000
memory locking and address space limit to unlimited
number of processes to 32768

You can do it by adding the following lines to the /etc/security/limits.conf file:

* - memlock unlimited
* - nofile 100000
* - nproc 32768
* - as unlimited

Last modified: 28 February 2018