Hi,

  I have a question on the amount of traffic ntop and libpcap can
handle, considering hardware specifications.  I have spanned 1Gb of
traffic the following linux system and ntop is reporting a large
amount of dropped traffic.  ntop eventually quits because it runs out
of hash table memory.  I suspect libpcap is dropping FIN packets and
as a result ntop keeps the conversation in memory.

  Given the hardware specifications below, how much traffic can I
expect ntop and libpcap handle?  When I look at the physical interface
I only see 100 drops.  ntop reports no drops.  The majority of dropped
traffic appears to be with libpcap.

CPU
Dual core Intel(R) Xeon(R) CPU            5140  @ 2.33GHz

Memory
:~# free
             total       used       free     shared    buffers     cached
Mem:       2075348    1873576     201772          0       7792    1417668
-/+ buffers/cache:     448116    1627232
Swap:      4000176         48    4000128

listening interface
eth1      Link encap:Ethernet  HWaddr
          inet6 addr: Scope:Link
          UP BROADCAST RUNNING PROMISC MULTICAST  MTU:1500  Metric:1
          RX packets:3678032734 errors:0 dropped:100 overruns:0 frame:0
          TX packets:6 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:618105664 (589.4 MiB)  TX bytes:492 (492.0 b)
          Interrupt:114 Memory:fa000000-fa011100

Kernel
2.6.18-6-686 #1 SMP Fri Jun 6 22:22:11 UTC 2008 i686 GNU/Linux

libpcap version
libpcap0.8-dev            0.9.5-1

ntop version
ntop v.3.3.8

>From the ntop Global Traffic page
Packets 
Dropped (libpcap)       115.8%  30,053,796
Dropped (ntop)  0.0%    0
Total Received (ntop)   25,955,606
Total Packets Processed 25,955,609
Unicast 100.0%  25,955,235
Broadcast       0.0%    7
Multicast       0.0%    355

-- 
Mike Marseglia
Systems Administrator, OSHEAN
401-886-0887 x208
401-248-4867
m...@oshean.org
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