OS User Limits

File Descriptor Limits
Process and Thread Limits

When running a large Oracle NoSQL Database store, the default OS limits may be insufficient. The following sections list limits that are worth reviewing.

File Descriptor Limits

Use ulimit -n to determine the maximum number of files that can be opened by a user. The number of open file descriptors may need to be increased if the defaults are too low. It's worth keeping in mind that each open network connection also consumes a file descriptor. Machines running clients as well as machines running RNs may need to increase this limit for large stores with 100s of nodes.

Add entries like the ones below in /etc/security/limits.conf to change the file descriptor limits:

$username soft nofile 10240
$username hard nofile 10240

where $username is the username under which the Oracle NoSQL Database software runs.

Note that machines hosting multiple replication nodes; that is, machines configured with a capacity > 1; will need larger limits than what is identified here.

Process and Thread Limits

Use ulimit -u to determine the maximum number of processes (threads are counted as processes under Linux) that the user is allowed to create. Machines running clients as well as machines running RNs may need to increase this limit to accommodate large numbers of concurrent requests.

Add entries like the ones below in /etc/security/limits.conf to change the thread limits:

$username soft nproc 8192
$username hard nproc 8192 

where $username is the username under which the Oracle NoSQL Database software runs.

Note that machines hosting multiple replication nodes; that is, machines configured with a capacity > 1; will need larger limits than what is identified here.