Типичные максимальные ошибки MySQL
/*
In the case of active connections using temporary/memory tables,
memory usage can go even higher.
On systems with small RAM or with a hard number of connections control on application side:
max_connections = 100-300.
Systems with 16G RAM or higher:
max_connections = 1000
Per-connection buffer should have good/default values while on some systems we can see
up to max_connections = 8000
*/
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