Cc: qemu-devel Eli Britstein <eli.britst...@toganetworks.com> writes:
> Hi > > In a VM, I add a IVSHMEM device, on which the MBUFS mempool resides, and also > rings I create (I run a DPDK application in the VM). > I saw there is a performance penalty if I use such device, instead of > hugepages (the VM's hugepages). My VM's memory is *NOT* backed with host's > hugepages. > The memory behind the IVSHMEM device is a host hugepage (I use a patched > version of QEMU, as provided by Intel). > I thought maybe the reason is that this memory is seen by the VM as a mapped > PCI memory region, so it is not cached, but I am not sure. > So, my direction was to change the kernel (in the VM) so it will consider > this memory as a regular memory (and thus cached), instead of a PCI memory > region. > However, I am not sure my direction is correct, and even if so, I am not sure > how/where to change the kernel (my starting point was mm/mmap.c, but I'm not > sure it's the correct place to start). > > Any suggestion is welcomed. > Thanks, > Eli.
