Free connections are checked over the time by sending senseless queries. Don't make this time too small - huge overhead for network. Don't make this time too big - you wouldn't able to detect failed connections due server restarting or e.t.c.
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Free connections are checked over the time by sending senseless queries. Don't make this time too small - huge overhead for network. Don't make this time too big - you wouldn't able to detect failed connections due server restarting or e.t.c.