> > Hi, > > > > The qemu process will stuck when hot-add large size memory to the > > virtual machine with a device passtrhough. > > We found it is too slow to pin and map pages in vfio_dma_do_map. > > Is there any method to improve this process? > > At what size do you start to see problems? The time to map a section of > memory should be directly proportional to the size. As the size is > increased, it will take longer, but I don't know why you'd reach a point > of not making forward progress. Is it actually stuck or is it just taking > longer than you want? Using hugepages can certainly help, we still need > to pin each PAGE_SIZE page within the hugepage, but we'll have larger > contiguous regions and therefore call iommu_map() less frequently. Please > share more data. Thanks, > > Alex It just take longer time, instead of actually stuck. We found that the problem exist when we hot-added 16G memory. And it will consume tens of minutes when we hot-added 1T memory.
Thanks, Wu Zongyong _______________________________________________ vfio-users mailing list vfio-users@redhat.com https://www.redhat.com/mailman/listinfo/vfio-users
