Re: Connections global server stats variable explanation

[Rick James]

SHOW GLOBAL STATUS LIKE 'Connections';
returns a counter. When a client connects, the counter is incremented. To use the value, divide by Uptime. A small sample of machines shows a median value of 2.2/sec; 90th percentile of 26/sec.

"max_connections" is the settable limit on the number of concurrent connections, not the counter above. 1500 is a moderately high value. It is often better to throttle the max in the client, rather than overwhelm mysql.

"Max_used_connections" is a high-water-mark for the number of concurrent connections. Median value: 120. If Max_used_connections reaches max_connections (or within 1), then client will be denied access (until a connection is closed).

See also Aborted_connects and Aborted_clients. Both are per second.

"Threads_running" is the number of connections doing something at the instant.

I don't know what "too many active scans" might mean. It does not quite sound like "table scans" (see Select_scan).

What values are you getting for the other things I mentioned? (Convert to /sec as needed.)