device_perf table removed: alert CPU usage > 90% for 5 minutes no longer works.

[mivsvit]

The alert %device_perf.avg >= "1000" no longer works as the device_perf table has been removed from LibreNMS and the data is now stored in an RRD instead.

The error

Error in alert rule CPU Latency > 500ms for 1 minute (8): SQLSTATE[42S02]: Base table or view not found: 1146 Table 'librenms.device_perf' doesn't exist (Connection: mysql, SQL: SELECT * FROM device_perf WHERE (devices.device_id = 16) AND device_perf.avg >= 1000)

is repeatedly generated.

See https://community.librenms.org/t/whats-happened-to-the-device-perf-table/24170/2