Re: [Xen-devel] Granularity of Credit and RTDS Scheduler

2017-01-14 Thread wy11
Thank you very much! Best Regards, Wenqiu Quoting Dario Faggioli : On Sun, 2017-01-08 at 22:06 +, Dario Faggioli wrote: Il 08 gen 2017 08:31, Meng Xu ha scritto: [cc. Dario and George] On Fri, Jan 6, 2017 at 1:34 PM, wy11 wrote: > Recently I read a paper about possible theft of service

Re: [Xen-devel] Granularity of Credit and RTDS Scheduler

2017-01-13 Thread Dario Faggioli
On Sun, 2017-01-08 at 22:06 +, Dario Faggioli wrote: > Il 08 gen 2017 08:31, Meng Xu ha scritto: > [cc. Dario and George] > On Fri, Jan 6, 2017 at 1:34 PM, wy11 wrote: > > Recently I read a paper about possible theft of service attacks in > Xen > > hypervisor. > > > > https://arxiv.org/pdf/11

Re: [Xen-devel] Granularity of Credit and RTDS Scheduler

2017-01-11 Thread wy11
Thank you very much.I really appreciate your help. Best Regards, Wenqiu Quoting Dario Faggioli : On Tue, 2017-01-10 at 15:32 -0600, wy11 wrote: If the time granularity of RTDS is nanosecond, then it is no longer a   problem. Can you please help me to know where I can find it in the   source

Re: [Xen-devel] Granularity of Credit and RTDS Scheduler

2017-01-11 Thread Dario Faggioli
On Tue, 2017-01-10 at 15:32 -0600, wy11 wrote: > If the time granularity of RTDS is nanosecond, then it is no longer > a   > problem. Can you please help me to know where I can find it in the   > source code? > If that's what you're interested in, time granularity is nanoseconds for each and every

Re: [Xen-devel] Granularity of Credit and RTDS Scheduler

2017-01-10 Thread Meng Xu
On Tue, Jan 10, 2017 at 4:32 PM, wy11 wrote: > Thank you very much for your explanation. > > To me, it seems to be an accounting problem because even if the time is > accounted immediately a VCPU wake up or sleeps, the problem remains if the > time is recorded in microseconds or million seconds be

Re: [Xen-devel] Granularity of Credit and RTDS Scheduler

2017-01-10 Thread wy11
Thank you very much for your explanation. To me, it seems to be an accounting problem because even if the time is accounted immediately a VCPU wake up or sleeps, the problem remains if the time is recorded in microseconds or million seconds because a VCPU can run for less than a unit so tha

Re: [Xen-devel] Granularity of Credit and RTDS Scheduler

2017-01-08 Thread Dario Faggioli
Il 08 gen 2017 08:31, Meng Xu ha scritto: [cc. Dario and George] On Fri, Jan 6, 2017 at 1:34 PM, wy11 wrote: > Dear Xen developers, Hi, > > Recently I read a paper about possible theft of service attacks in Xen > hypervisor. > > https://arxiv.org/pdf/1103.0759.pdf I quickly read it. It is int

Re: [Xen-devel] Granularity of Credit and RTDS Scheduler

2017-01-07 Thread Meng Xu
[cc. Dario and George] On Fri, Jan 6, 2017 at 1:34 PM, wy11 wrote: > Dear Xen developers, Hi, > > Recently I read a paper about possible theft of service attacks in Xen > hypervisor. > > https://arxiv.org/pdf/1103.0759.pdf I quickly read it. It is interesting to see that EC2 suffers from such

[Xen-devel] Granularity of Credit and RTDS Scheduler

2017-01-07 Thread wy11
Dear Xen developers, Recently I read a paper about possible theft of service attacks in Xen hypervisor. https://arxiv.org/pdf/1103.0759.pdf Due to the 10 ms intervals between sampling points, a malicious VM is able to run less than a interval and sleep to avoid being accounted. According