System swaps with free memory.

[bagas]

Hello.
The system swaps with free memory.

Mem: 284M Active, 8560K Inact, 1928M Wired, 1572M Buf, 29G Free
Swap: 4096M Total, 2891M Used, 1205M Free, 70% Inuse, 10M In, 5584K Out

  PID USERNAME    THR PRI NICE   SIZE    RES STATE   C   TIME    WCPU COMMAND
15598 mysql        88  20    0  9203M   289M select  4   6:49  16.21% [mysqld]
15762 root          1  20    0  7916K  1112K CPU5    5   0:00   0.02% top -Pa

Why is this happening?
Memory free is full.
I tried to do it.
swapoff -a && swapon -a
But still it goes back to the swap.

 

[bagas]

Understood, the problem was in this parameter vm.v_free_target