The database memory is not released

Dear all,

I have some issue regarding to the database, the anon kernel of database usage memory increase day by day and not release until we restart the application on weblogic server.

You can see below:

# echo "::memstat" | mdb -k

Page Summary                 Pages             Bytes  %Tot

----------------- ----------------  ----------------  ----

Kernel                     1729232             13.1G    5%

Guest                            0                 0    0%

ZFS Metadata                105465            823.9M    0%

ZFS File Data             20432060            155.8G   61%

Anon                      10167538             77.5G   30%

Exec and libs                29079            227.1M    0%

Page cache                   10757             84.0M    0%

Free (cachelist)              4431             34.6M    0%

Free (freelist)            1075870              8.2G    3%

Total                     33554432              256G

Yesterday it was just 28%, It will increase 2 or 3% a day after end of cycle.

Anyone knows how to solve this ? or there's only the option to restart the front-end ?