ip_conntrack problem with memcached

[Hansflug (at) freenet]

Hello,

i have a Problem with my Connection to memcached.
in peaktime the kernel log show that i have a ip_conntrack problem ?
i use php5 and memcachelib for save db results. 

What tuning i can do for my problem  ????

here information about my memcache daemon.....
the server no swapping or have no high load. but i have many
connections !!

server:
2 CPU but memcache use only one....
2GB RAM
load average: 0.08, 0.09, 0.09
Cpu(s):  1.3% us,  2.5% sy,  0.0% ni, 94.3% id,  0.0% wa,  0.3% hi,
1.5% si
Mem:   2077052k total,  1943424k used,   133628k free,   100344k buffers
Swap:  3148720k total,        0k used,  3148720k free,   285896k cached


kernel.log

kernel: ip_conntrack: table full, dropping packet.
last message repeated 9 times
kernel: printk: 3815 messages suppressed.
...................
./memcached-tool localhost:11516 display
 6         B      0 s       0     yes
  7         B      0 s       0     yes
  8     256 B  44405 s       8     yes
  9     512 B  48126 s      12     yes
 10      1 kB  51820 s       1     yes
 11      2 kB  38461 s     130     yes
 12      4 kB  42341 s     117     yes
 13      8 kB  39478 s     229     yes
 14     16 kB  59783 s       2     yes
 15     32 kB 833888 s       1      no
 16         B      0 s       0     yes
 17         B      0 s       0     yes

startparameter
/usr/bin/memcached -m 500 -p 11516 -u root -c 4500

statsinfo
telnet localhost 11516
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
stats
STAT pid 9639
STAT uptime 1532210
STAT time 1163406727
STAT version 1.1.12
STAT rusage_user 16376.415406
STAT rusage_system 28586.777149
STAT curr_items 184292
STAT total_items 125758879
STAT bytes 343284616
STAT curr_connections 547
STAT total_connections 43200011
STAT connection_structures 3253
STAT cmd_get 346041673
STAT cmd_set 125758879
STAT get_hits 304561195
STAT get_misses 41480478
STAT bytes_read 90234189974
STAT bytes_written 402886887964
STAT limit_maxbytes 524288000