system slow when plugged to network

[albator]

Hi,

Since yesterday night my system has been reacting very slowly without I could find out why.

In fact, If I unplugged the network cable (leading to the Internet Box) or stop dhclient then everything is back to normal.
For example, opening programms like Keepass, Terminal, Gvim may take up to 10s and surfing the Net is dead slow.
The same thing happens with my netbook.
I changed dhcp for statics address whithout any success.
I thought it was due to my Internet Box, but my third netbook with FreeBSD is not affected by this behavior and I wonder why it affects programs that don't connect to Internet.

Example while opening Keepass :

$ keepassx &  vmstat 2 10
[1] 8129
 procs    memory       page                    disks    traps          cpu
 r b w    avm     fre  flt  re  pi  po  fr  sr sd0 sd1  int   sys   cs us sy id
 2 1 0 349352 10955632  181   0   0   0   0   0   1   1   11  3156  340  1  1 98
 0 1 0 353912 10950296 3191   0   0   0   0   0   0   0    9 12194  437  7  1 91
 1 1 0 353928 10950280   42   0   0   0   0   0   0   0    4  1592  223  0  0 100
 0 1 0 353912 10950296   45   0   0   0   0   0   0   0   16  1630  247  0  0 100
 0 1 0 353920 10950288   41   0   0   0   0   0   0   0    6  1602  228  0  0 99
 0 1 0 353912 10950296   41   0   0   0   0   0   0   0    4  1721  226  0  0 100
 0 1 0 353936 10950272   45   0   0   0   0   0   0   0   15  1621  231  0  0 100
 0 1 0 353948 10950260   44   0   0   0   0   0   0   0    3  1710  216  1  0 99 -> Keepass opens here
 1 1 0 353928 10950280   40   0   0   0   0   0   0   0    0  1498  212  0  0 100
 0 1 0 365496 10938340 4845   0   0   0   0   0   0   0    2 17389 1291  9  4 87

$ uname -a
OpenBSD LNBoX.my.domain 5.4 GENERIC.MP#0 amd64

$ ifconfig re0
re0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
        priority: 0
        groups: egress
        media: Ethernet autoselect (100baseTX full-duplex)
        status: active
        inet6 fe80::1e6f:65ff:fe81:bfe4%re0 prefixlen 64 scopeid 0x1
        inet 192.168.0.10 netmask 0xffffff00 broadcast 192.168.0.255

$ netstat -ni
Name    Mtu   Network     Address              Ipkts Ierrs    Opkts Oerrs Colls
lo0     33144 <Link>                              14     0       14     0     0
lo0     33144 ::1/128     ::1                     14     0       14     0     0
lo0     33144 fe80::%lo0/ fe80::1%lo0             14     0       14     0     0
lo0     33144 127/8       127.0.0.1               14     0       14     0     0
re0     1500  <Link>      		       24214     0    22226     0     0
re0     1500  fe80::%re0/ fe80::1e6f:65ff:f    24214     0    22226     0     0
re0     1500  192.168.0/2 192.168.0.10         24214     0    22226     0     0
enc0*   0     <Link>                               0     0        0     0     0
pflog0  33144 <Link>                               0     0        0     0     0

$ dmesg|grep re0           
re0 at pci3 dev 0 function 0 "Realtek 8168" rev 0x03: RTL8168D/8111D (0x2800), apic 2 int 18,

I didn't find errors in /var/log and I didn't change anything in the system.

Any ideas ?

Thank you