hi, Andreas thank you very much for your answers! I'm sorry that i reply so late. I don't know how to use the EtherTap object in gem5 to communicate with the out world and I will try it first. Now I have no idea how to get the meaningful results under the situation that the simulator and the real world have big difference in their speed. Do you have some suggestions?
zhangyi From: Andreas Sandberg Date: 2013-07-12 00:06 To: gem5 Developer List Subject: Re: [gem5-dev] Does gem5 instance (ARM FS) support communicating with outside real world? There is actually supposed to be support for this in the simulator already. There is an object called EtherTap that interfaces a virtual ethernet device to a Linux Tap device (virtual ethernet device) which can be bridged with a real device. The Tap interface is actually used by software like Qemu to interface with the rest of the world. I haven't used it myself (in fact I haven't tried to use any of the network devices in gem5 and I don't know of anyone who has, so I'm not sure that it works. As Andreas already pointed out, you'll probably have a hard time to get meaningful results from your simulations if you use this since there will be a significant speed difference between the real world and the simulated world. You might be able to get the atomic CPU to run fast enough to get things to work. //Andreas On 07/11/2013 02:54 PM, Andreas Hansson wrote: > Hi Zhangyi, > > gem5 does currently not support any interaction with the host-side > ethernet. It would be a very valuable addition (although it would make > simulations non-deterministic), and the tricky bit is the big speed > difference between the guest and the host. TCP/IP has a lot of timers that > would cause havoc if you simply tried to bridge the interfaces (like e.g. > vmware, parallels and virtualbox does). If you want to start working on a > gem5 guest/host-ethernet bridge, I'd say go ahead and kick off a > discussion about the design. I'm sure there's plenty people out there with > ideas. > > When it comes to your second question it is also not available today. > Someone would have to implement an ethernet switch. This should not be too > complex (far easier than the bridge above) and would also be a very > welcome addition to the toolbox. > > In short: great ideas, we just need someone to actually do it. > > Andreas > > > On 11/07/2013 09:10, "zhangyi"<[email protected]> wrote: > >> Hi,all >> >> >> We have a need that simulated FS ARM communicates with other real hosts >> through ethernet. I don't know if gem5 supports that right now. If >> doesn't, how can I try to make it? Is there anyone having ideas about >> this problem? >> >> >> Besides, I know that the gem5 supports --dual args, with which booting >> two instances linked by a etherlink can be possible. Can gem5 supports >> three or more instances connected in a ethernet? >> >> >> Any answers will be appreciated! >> >> >> >> >> zhangyi >> _______________________________________________ >> gem5-dev mailing list >> [email protected] >> http://m5sim.org/mailman/listinfo/gem5-dev >> > > -- IMPORTANT NOTICE: The contents of this email and any attachments are > confidential and may also be privileged. If you are not the intended > recipient, please notify the sender immediately and do not disclose the > contents to any other person, use it for any purpose, or store or copy the > information in any medium. Thank you. > > _______________________________________________ > gem5-dev mailing list > [email protected] > http://m5sim.org/mailman/listinfo/gem5-dev _______________________________________________ gem5-dev mailing list [email protected] http://m5sim.org/mailman/listinfo/gem5-dev _______________________________________________ gem5-dev mailing list [email protected] http://m5sim.org/mailman/listinfo/gem5-dev
