Stefano, Brilliant job! I can confirm that with these patches the memory footprint is smaller and the boot time is the same for kata
Here the results using kata metrics https://pasteboard.co/Ipl06Q0.png https://pasteboard.co/Ipl3p4d.png Thanks - Julio On Tue, 2019-07-23 at 16:04 +0200, Stefano Garzarella wrote: > In order to reduce the memory footprint when PVH kernel and initrd > are used, we map them into memory instead of reading them. > In this way we can share them between multiple instances of QEMU. > > v2: > - Patch 1: used g_mapped_file_new_from_fd() with 'writeble' set to > 'true', > since we can modify the mapped buffer. [Paolo, Peter] > > These are the results using a PVH kernel and initrd (cpio): > - memory footprint (using smem) [MB] > QEMU before now > # instances USS PSS USS PSS > 1 102.0M 105.8M 102.3M 106.2M > 2 94.6M 101.2M 72.3M 90.1M > 4 94.1M 98.0M 72.0M 81.5M > 8 94.0M 96.2M 71.8M 76.9M > 16 93.9M 95.1M 71.6M 74.3M > > Initrd size: 3.0M > Kernel > image size: 28M > sections size [size -A -d vmlinux]: 18.9M > > - boot time [ms] > before now > qemu_init_end: 63.85 55.91 > linux_start_kernel: 82.11 (+18.26) 74.51 (+18.60) > linux_start_user: 169.94 (+87.83) 159.06 (+84.56) > > QEMU command used: > ./qemu-system-x86_64 -bios /path/to/seabios/out/bios.bin -no-hpet \ > -machine > q35,accel=kvm,kernel_irqchip,nvdimm,sata=off,smbus=off,vmport=off \ > -cpu host -m 1G -smp 1 -vga none -display none -no-user-config > -nodefaults \ > -kernel /path/to/vmlinux -initrd /path/to/rootfs.cpio \ > -append 'root=/dev/mem0 ro console=hvc0 pci=lastbus=0 nosmap' > > Stefano Garzarella (2): > elf-ops.h: Map into memory the ELF to load > hw/i386/pc: Map into memory the initrd > > hw/i386/pc.c | 15 ++++++++--- > include/hw/elf_ops.h | 64 ++++++++++++++++++++++++---------------- > ---- > 2 files changed, 46 insertions(+), 33 deletions(-) >
