Re: Table freeze when size exceeds innodb buffer pool size

[Peter Brawley]

The main thing: Select_scan > 1/sec, next-row requests > 1200/sec; there are way too many queries requiring table scans. Turn on the slow query log, find those offending queries, run Explain on them, optimise them so they use indexes.

Your 5.1 version of MySQL is nine years old. You need to migrate -> 5.5 -> 5.6 ->5.7, which has much more advancecdquery optimisation.

Other points:

InnoDB log files are being rotated every 6.5 hours, ~30 min is usually preferable, try shrinking the logs

The InnoDB buffer pool appears to be running 50% free, so you could try shrinking it too.