Dear Sir, I am writing to thank you for your letter and say,
On Mon, Oct 11, 2004 at 01:48:17PM -0500, Joe Carder wrote: > After having the mirroring port on our core switch take down our core switch > I moved our ntop box to a switch that is outside our firewall that sees > allot less traffic. The switch is doing fine but I am still having a > problem with libpcap dropping packets. When the box was on our core switch > I say libpcap dropping roughly 80% of the packets, now I am seeing roughly > 50% of the packets being dropped. I know this isn't necessarily a problem > with ntop but I was wondering if anyone on the list might have any > recommendation on getting libpcap's drop ratio down. Thanks in advance for > any help. > > > > Here are the system specs: > > Dell GL250: > > 2.5 GHZ Pentium III > > 512 megs of ram > > > > OS: Freebsd 5.2.1 that in view of the fact you are using a not yet stable branch of FreeBSD and the thread entitled 'Packet passing performance study on exotic hardware.' on the FreeBSD stable lists (eg http://docs.freebsd.org/cgi/getmsg.cgi?fetch=148683+0+archive/2004/freebsd-stable/20041010.freebsd-stable ) this OS may not be a good choice for Ntop. I am not knowledgable about OSs or FreeBSD, but this article states 'Right out of the box (with polling), Linux passed 550 kpps (kilo packets wer second). Full data rate would be 1.9 mpps. On linux, the 240 processors passed only 450 kppps (which is somewhat expected). Right out of the box, FreeBSD 5.3 (with polling) passed about 200 kpps. net.isr.enable=1 increased that without polling to about 220 kpps (although livelock ensued without polling as packet load increased). With excessive tuning, we got FreeBSD 5.3 to pass 270 kpps. This included polling, nmbclusters, net.isr, and some em patches. I can't see where to get more performance. To compare, we loaded FreeBSD-5.3 ia32 and achieved almost identical performance. Then, also to compare, we loaded FreeBSD-4.10 ia32 and it promptly passed 550 kpps (almost identical to the linux performance) (with polling). ' If Ntop performance is your only concern, You may be better off with Linux or FreeBSD 4.x-RELEASE. Yours ssincerely. -- Stanley Hopcroft Network specialist, IT Infrastructure IP Australia Ph: (02) 6283 3189 Fax: (02) 6281 1353 PO Box 200 Woden ACT 2606 http://www.ipaustralia.gov.au _______________________________________________ Ntop mailing list [EMAIL PROTECTED] http://listgateway.unipi.it/mailman/listinfo/ntop
