why my virtual memory still increasing when openldap is running?

["何萍" <cress.hp@gmail.com>]

openldap: 2.0.17 ; OS: RH9.0

 

my virtual memory still increasing , no matter what operation i did, such as search/add/modify.

 

the top result is:

Mem:  3608380k av, 3218344k used,  390036k free,       0k shrd,   82776k buff
                   2062984k actv,   56724k in_d,   97036k in_c
Swap: 3124560k av,    5312k used, 3119248k free                 2868164k cached

  PID USER     PRI  NI  SIZE  RSS SHARE STAT %CPU %MEM   TIME CPU COMMAND
 9415 root      15   0  122M 122M  1156 S     3.7  3.4   1:22   3 slapd

and it quickly to 500M,  when the system's memory near to 10M, openldap could not work properly