Re: [gentoo-performance] TCP perfomance
Miguel Sousa Filipe wrote: On Fri, Jun 6, 2008 at 6:26 PM, Kevin Faulkner <[EMAIL PROTECTED]> wrote: Miguel Sousa Filipe wrote: There is no such thing has a TCP timestamp: http://freebie.fatpipe.org/~mjb/Drawings/TCP_Header.png so, that doesn't make any sense... Your right and I'm wrong. Its not in the header, its thrown on at the end ...at the end of the tcp header, it's a tcp option. (I didn't understood that the first time I read this email). It might be good to disable all tcp optional headers.. Also there might be important to look at issues such has: - mtu size - tcp window - set the don't fragment flag (this can offload the routers and optimize the mtu for the whole connection path) - use the BIC algorithm (from what I've read, that's my default choice nowadays... but for some specific workload there might be better algorithms) I haven't played around with different congestion algorithms all that much, I generally have stuck with Westwood. MTU size... with all the different machines we have, I prefer to stay with the default. Window size is a good point. try doing cat /proc/sys/net/ipv4/tcp_timestamps http://www.networksorcery.com/enp/protocol/tcp/option008.htm http://www.securiteam.com/securitynews/5NP0C153PI.html kind regards! sorry if I seemed rude. heh, text can come across like that sometimes. -- gentoo-performance@lists.gentoo.org mailing list
Re: [gentoo-performance] TCP perfomance
Miguel Sousa Filipe wrote: There is no such thing has a TCP timestamp: http://freebie.fatpipe.org/~mjb/Drawings/TCP_Header.png so, that doesn't make any sense... Your right and I'm wrong. Its not in the header, its thrown on at the end try doing cat /proc/sys/net/ipv4/tcp_timestamps http://www.networksorcery.com/enp/protocol/tcp/option008.htm http://www.securiteam.com/securitynews/5NP0C153PI.html -- gentoo-performance@lists.gentoo.org mailing list
[gentoo-performance] TCP perfomance
Yes, I also forgot that I had been subscribed to this list. To get a topic going I was at work and I argued that we should disable TCP timestamps. I was discussing in a meeting that this would cut back (perhaps very slightly) on the amount of work that the system has to do before sending a packet out. In a high traffic system (like a file server or a mail server or in my case a Oracle Database), not having to throw this on every packet should increase performance ever so slightly. Disabling this would benefit security, as the attacker would not be able to gather the up time from the targeted system. Like I said this might be a slight increase, but its an increase none-the-less, and when you have a DBA crying about poor network speed or IO, or the system is too heavily loaded, then this keeps him quiet for a few days. :) Any thoughts??? -- gentoo-performance@lists.gentoo.org mailing list
Re: [gentoo-performance] unsubscribe
Alex Howells wrote: I do have to wonder why all the ricers on -performance can't RTFM to the point they can even unsubscribe. Is this an accurate representation of all the users of this mailing list? :P They can't read because they're going to _fast_!!! -- gentoo-performance@lists.gentoo.org mailing list
