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cockroachdb_open_file_descriptors_limit

cockroachdb_open_file_descriptors_limit

Database | CockroachDB

This is an alert about the Cockroach Database. The Netdata Agent calculates the percentage of used file descriptors. This alert indicates high file descriptors utilization (against soft limit). To fix this issue, adjust the per process or system-wide file descriptors limit.

This alert is triggered in warning state when the file descriptors utilization is more than 80%.

See more about hard limits and soft limits

A hard limit can only be raised by root (any process can lower it). So it is useful for security: a non-root process cannot overstep a hard limit. But it’s inconvenient in that a non-root process can’t have a lower limit than its children.

A soft limit can be changed by the process at any time. So it’s convenient as long as processes cooperate, but no good for security.

A typical use case for soft limits is to disable core dumps ulimit -Sc 0 while keeping the option of enabling them for a specific process you’re debugging ulimit -Sc unlimited; myprocess. The ulimit shell command is a wrapper around the setrlimit system call, so that’s where you’ll find the definitive documentation. 1

Note that some systems may not implement all limits, Linux kernel does. Specifically, some systems don’t support
per-process limits on file descriptors.

References and sources

[1] https://unix.stackexchange.com/questions/29577/ulimit-difference-between-hard-and-soft-limits