On 26/11/2019 11:31, Ilya Maximets wrote: > 'dpdkr' a.k.a. DPDK ring ports has really poor support in OVS and not > tested on a regular basis. These ports are intended to work via > shared memory with another DPDK secondary process, but there are lots > of limitations for using this functionality in practice. Most of them > connected with running secondary DPDK application and memory layout > issues. More details are available in DPDK guide: > https://doc.dpdk.org/guides/prog_guide/multi_proc_support.html#multi-process-limitations > > Beside the functional limitations it's also hard to use this > functionality correctly. User must be sure that OVS and secondary DPDK > application are running on different CPU cores, which is hard because > non-PMD threads could float over available CPU cores. This or any > other misconfiguration will likely lead to crash of OVS. > > Another problem is that the user must actually build the secondary > application with the same version of DPDK that was used for OVS build. > > Above issues are same as we have while using DPDK pdump. > > Beside that, current implementation in OVS is not able to free > allocated rings that could lead to memory exhausting. > > Initially these ports was added to use with IVSHMEM for a fast > zero-copy HOST<-->VM communication. However, IVSHMEM is not used > anymore. IVSHMEM support was removed from DPDK in 16.11 relase and > the patch for QEMU for using regular files as a device backend is no > longer available. That makes DPDK ring ports barely useful in real > virtualization environment. >
You could also reference that instructions for ivshmem were removed from the OVS docs almost 3 years ago. 90ca71dd317f ("doc: Remove ivshmem instructions.") > This patch adds a deprecation warnings for run-time port creation > and documentation. Claiming to completely remove this functionality > from OVS in one of the next releases. > > Signed-off-by: Ilya Maximets <i.maxim...@ovn.org> > --- Acked-by: Kevin Traynor <ktray...@redhat.com> _______________________________________________ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev