On Fri, 4 Mar 2011 22:53:30 +0900 Ryan McBride <mcbr...@openbsd.org> wrote:
>| On Thu, Mar 03, 2011 at 03:52:54PM +0100, Manuel Guesdon wrote: >| > >| I think we already mentioned it that you will always see Ierr. The >| > >| question is if the box is able to forward more then 150kpps. >| > >| > Yes that's one a the questions. We can divide it into 3 questions: >| > 1) is the limitation comes from hardware ? >| > 2) is the limitation comes from OpenBSD ? >| > 3) is the limitation comes from the way OpenBSD exploit hardware. >| > >| > 1) Except if someone explain by a+b why the hardware can't forward this >| > rate, I'm keep thinking it can do it (otherwise I don't see reason to sell >| > quad 1Gbps nic). >| >| Are you suggesting that because you have a quad-port gig nic, your box >| should be able to do 6 *million* packets per second? By that logic my >| 5-port Soekris net4801 should be able to handle 740kpps. (for reference, >| the net4801 does about 3kpps with 4.9) No, I don't suggest that, I simply think it strange to have these kind of hardware specification (bus length and speed and bgps nic) and can't handle something like 160kpps in packets when the 'only' (i.e. no userland application) job of the server is to forward packets and that server seems to be >90% idle. >| > I'm ok to hear that I've purchased crappy motherboard card >| > or nic (but I'd like to understand why they are crappy). >| >| It has nothing to do with hardware crappiness, it has to do with your >| expectations. Your box should certainly be able to fill a few of your >| gig ports with 1500byte packets, but there is no way it'll handle a full >| 4 gigabits / second of TCP syn packets. I don't expect that numbers. >| > I've spent days and days making tests, searches, reading kernel source >| > code and so on because I think it's interesting for the community to >| > find where the problem come from and how to solve it (if possible). If >| > finally the answer is that OpenBSD (or may be any other OS) can't >| > forward more than 150kpps without losing 1 to 20 pps with this >| > hardware, I'll live with it. >| >| Are you actually complaining about 1 to 20 errors per second? That's >| 0.01% packet loss, welcome to ethernet. You will not see this change by >| switching to different hardware or OS. I'm not complaining, I just try to see if it's 'normal' to have these loss when server seems not very loaded or if it hide a problem. >| It /is/ possible that something is wrong with your box and you could be >| getting a slightly higher throughput. But don't expect that we'll make >| it handle 2 million PPS any time soon. Once again, I don't expect forwarding 2Mpps nor 4Gbps. >| However, don't bother just telling us "there's something to improve". >| We've working on this for years, we've already made huge improvements, >| and we're always looking for more. Perhaps the biggest limitation on >| modern hardware is that we can't split the packet handling across >| multiple CPUs, but your "input" provides exactly ZERO help with changing >| that. Please see my previous messages: I've never said "I see Ierrs, please fix it". Claudio suggested a possible mbuf leak problem and I've asked how can I try to confirm (or not) that. You've also pointed out high livelocks value so I've understood it as there's may be something wrong somewhere. I've provided requested information to help us trying to see if there's a problem or not. I'm not hardware expert, not driver expert and even not OpenBSD expert, I just try to understand and may be help improving things; All my apologies if my previous messages didn't reflect that. Manuel -- ______________________________________________________________________ Manuel Guesdon - OXYMIUM
