Snort mailing list archives
Re: BPF/libpcap performance, was Re: Seg Fault
From: Jeff Nathan <jeff () snort org>
Date: Tue, 26 Feb 2002 18:20:21 -0800
Erek Adams wrote:
On Tue, 26 Feb 2002, Chris Green wrote:If you are running linux on your IDS stuff, its worth it for hearing about the things they do to turbo packet stuff now and then.Naaa... I'm not quite that brave yet.I'm sure there are things like memcaps for bpf and the like to set and I'd love to see a good technical paper other than the winpcap one on pcap performance's as well as tuning.Hrm...I'm also pretty sure one of the security websites would even pay a bit for an article on tuning of pcap performance. Most everything I've seen in the past few years ranks right above voodoo.Hey, I'm from Louisiana so I gotta believe in voodoo! :) ----- Erek Adams Nifty-Type-Guy TheAdamsFamily.Net
Be forewarned, I'm making a stab in the dark here. BSD IP stacks store packets in clusters of mbufs which are sized statically. I looked through the OpenBSD i386 headers and the size of the default mbuf is 256 and the cluster size is 2048 bytes, which is large enough to store an entire Ethernet frame. Under OpenBSD (and I suspect all the BSDs), you can change the number of clusters available to your stack in your kernel configuration. A fairly high amount of clusters might be something like 8192 if you're REALLY worried about running out. I belive the default value at this point is 2048. How does this end up effecting bpf... that's another story altogether (I have pretty much *no* idea). Your mileage may vary. -Jeff -- http://jeff.wwti.com (pgp key available) "Common sense is the collection of prejudices acquired by age eighteen." - Albert Einstein _______________________________________________ Snort-users mailing list Snort-users () lists sourceforge net Go to this URL to change user options or unsubscribe: https://lists.sourceforge.net/lists/listinfo/snort-users Snort-users list archive: http://www.geocrawler.com/redir-sf.php3?list=snort-users
Current thread:
- Re: Seg Fault, (continued)
- Re: Seg Fault Demetri Mouratis (Feb 23)
- RE: Seg Fault neptuna (Feb 24)
- RE: Seg Fault neptuna (Feb 24)
- Re: Seg Fault spyguy703 (Feb 26)
- Re: Seg Fault Chris Green (Feb 26)
- Re: BPF/libpcap performance, was Re: Seg Fault Erek Adams (Feb 26)
- Re: BPF/libpcap performance, was Re: Seg Fault Ashley Thomas (Feb 26)
- Re: BPF/libpcap performance, was Re: Seg Fault Erek Adams (Feb 26)
- Re: Seg Fault Demetri Mouratis (Feb 23)
- Re: BPF/libpcap performance, was Re: Seg Fault Chris Green (Feb 26)
- Re: BPF/libpcap performance, was Re: Seg Fault Erek Adams (Feb 26)
- Re: BPF/libpcap performance, was Re: Seg Fault Jeff Nathan (Feb 26)
- What's going on with www.snort.org? Paul Farley (Feb 27)
- Re: BPF/libpcap performance, was Re: Seg Fault Phil Wood (Feb 26)