Public bug reported: I created system with 7 NUMA nodes where nodes 0-3 should have 268435456 bytes size and nodes 4-6 exactly 1610612736 bytes size, but when I run "numactl -H" I got different (smaller) sizes. It is essential for me to be able to emulate a system with nodes of exact size - is it possible?
QEMU version: QEMU emulator version 5.1.0 Copyright (c) 2003-2020 Fabrice Bellard and the QEMU Project developers QEMU command: qemu-system-x86_64 -hda qemu-image/ubuntu-1804.img -enable-kvm -cpu Cascadelake-Server -vnc :5 -netdev user,id=net0,hostfwd=tcp::10022-:22 -device virtio-net,netdev=net0 -boot c -m 5632.0M -object memory- backend-ram,id=ram-node0,size=268435456 -numa node,nodeid=0,cpus=0-3,memdev=ram-node0 -object memory-backend-ram,id =ram-node1,size=268435456 -numa node,nodeid=1,cpus=4-7,memdev=ram-node1 -object memory-backend-ram,id=ram-node2,size=268435456 -numa node,nodeid=2,cpus=8-11,memdev=ram-node2 -object memory-backend-ram,id =ram-node3,size=268435456 -numa node,nodeid=3,cpus=12-15,memdev=ram- node3 -object memory-backend-ram,id=ram-node4,size=1610612736 -numa node,nodeid=4,memdev=ram-node4 -object memory-backend-ram,id=ram- node5,size=1610612736 -numa node,nodeid=5,memdev=ram-node5 -object memory-backend-ram,id=ram-node6,size=1610612736 -numa node,nodeid=6,memdev=ram-node6 -numa dist,src=0,dst=0,val=10 -numa dist,src=0,dst=1,val=21 -numa dist,src=0,dst=2,val=31 -numa dist,src=0,dst=3,val=21 -numa dist,src=0,dst=4,val=17 -numa dist,src=0,dst=5,val=38 -numa dist,src=0,dst=6,val=28 -numa dist,src=1,dst=0,val=21 -numa dist,src=1,dst=1,val=10 -numa dist,src=1,dst=2,val=21 -numa dist,src=1,dst=3,val=31 -numa dist,src=1,dst=4,val=28 -numa dist,src=1,dst=5,val=17 -numa dist,src=1,dst=6,val=38 -numa dist,src=2,dst=0,val=31 -numa dist,src=2,dst=1,val=21 -numa dist,src=2,dst=2,val=10 -numa dist,src=2,dst=3,val=21 -numa dist,src=2,dst=4,val=28 -numa dist,src=2,dst=5,val=28 -numa dist,src=2,dst=6,val=28 -numa dist,src=3,dst=0,val=21 -numa dist,src=3,dst=1,val=31 -numa dist,src=3,dst=2,val=21 -numa dist,src=3,dst=3,val=10 -numa dist,src=3,dst=4,val=28 -numa dist,src=3,dst=5,val=28 -numa dist,src=3,dst=6,val=17 -numa dist,src=4,dst=0,val=17 -numa dist,src=4,dst=1,val=28 -numa dist,src=4,dst=2,val=28 -numa dist,src=4,dst=3,val=28 -numa dist,src=4,dst=4,val=10 -numa dist,src=4,dst=5,val=28 -numa dist,src=4,dst=6,val=28 -numa dist,src=5,dst=0,val=38 -numa dist,src=5,dst=1,val=17 -numa dist,src=5,dst=2,val=28 -numa dist,src=5,dst=3,val=28 -numa dist,src=5,dst=4,val=28 -numa dist,src=5,dst=5,val=10 -numa dist,src=5,dst=6,val=28 -numa dist,src=6,dst=0,val=38 -numa dist,src=6,dst=1,val=28 -numa dist,src=6,dst=2,val=28 -numa dist,src=6,dst=3,val=17 -numa dist,src=6,dst=4,val=28 -numa dist,src=6,dst=5,val=28 -numa dist,src=6,dst=6,val=10 -smp 16,sockets=4,dies=1,cores=4,threads=1 -fsdev local,security_model=passthrough,id=fsdev0,path=/home/mysuser/share -device virtio-9p-pci,id=fs0,fsdev=fsdev0,mount_tag=share_host -daemonize output from numactl -H: $ numactl -H available: 7 nodes (0-6) node 0 cpus: 0 1 2 3 node 0 size: 250 MB node 0 free: 191 MB node 1 cpus: 4 5 6 7 node 1 size: 251 MB node 1 free: 199 MB node 2 cpus: 8 9 10 11 node 2 size: 251 MB node 2 free: 218 MB node 3 cpus: 12 13 14 15 node 3 size: 251 MB node 3 free: 118 MB node 4 cpus: node 4 size: 1511 MB node 4 free: 1507 MB node 5 cpus: node 5 size: 1447 MB node 5 free: 1443 MB node 6 cpus: node 6 size: 1489 MB node 6 free: 1484 MB node distances: node 0 1 2 3 4 5 6 0: 10 21 31 21 17 38 28 1: 21 10 21 31 28 17 38 2: 31 21 10 21 28 28 28 3: 21 31 21 10 28 28 17 4: 17 28 28 28 10 28 28 5: 38 17 28 28 28 10 28 6: 38 28 28 17 28 28 10 ** Affects: qemu Importance: Undecided Status: New -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1912170 Title: NUMA nodes created with memory-backend-ram shows size different than requested Status in QEMU: New Bug description: I created system with 7 NUMA nodes where nodes 0-3 should have 268435456 bytes size and nodes 4-6 exactly 1610612736 bytes size, but when I run "numactl -H" I got different (smaller) sizes. It is essential for me to be able to emulate a system with nodes of exact size - is it possible? QEMU version: QEMU emulator version 5.1.0 Copyright (c) 2003-2020 Fabrice Bellard and the QEMU Project developers QEMU command: qemu-system-x86_64 -hda qemu-image/ubuntu-1804.img -enable-kvm -cpu Cascadelake-Server -vnc :5 -netdev user,id=net0,hostfwd=tcp::10022-:22 -device virtio-net,netdev=net0 -boot c -m 5632.0M -object memory- backend-ram,id=ram-node0,size=268435456 -numa node,nodeid=0,cpus=0-3,memdev=ram-node0 -object memory-backend-ram,id =ram-node1,size=268435456 -numa node,nodeid=1,cpus=4-7,memdev=ram- node1 -object memory-backend-ram,id=ram-node2,size=268435456 -numa node,nodeid=2,cpus=8-11,memdev=ram-node2 -object memory-backend-ram,id =ram-node3,size=268435456 -numa node,nodeid=3,cpus=12-15,memdev=ram- node3 -object memory-backend-ram,id=ram-node4,size=1610612736 -numa node,nodeid=4,memdev=ram-node4 -object memory-backend-ram,id=ram- node5,size=1610612736 -numa node,nodeid=5,memdev=ram-node5 -object memory-backend-ram,id=ram-node6,size=1610612736 -numa node,nodeid=6,memdev=ram-node6 -numa dist,src=0,dst=0,val=10 -numa dist,src=0,dst=1,val=21 -numa dist,src=0,dst=2,val=31 -numa dist,src=0,dst=3,val=21 -numa dist,src=0,dst=4,val=17 -numa dist,src=0,dst=5,val=38 -numa dist,src=0,dst=6,val=28 -numa dist,src=1,dst=0,val=21 -numa dist,src=1,dst=1,val=10 -numa dist,src=1,dst=2,val=21 -numa dist,src=1,dst=3,val=31 -numa dist,src=1,dst=4,val=28 -numa dist,src=1,dst=5,val=17 -numa dist,src=1,dst=6,val=38 -numa dist,src=2,dst=0,val=31 -numa dist,src=2,dst=1,val=21 -numa dist,src=2,dst=2,val=10 -numa dist,src=2,dst=3,val=21 -numa dist,src=2,dst=4,val=28 -numa dist,src=2,dst=5,val=28 -numa dist,src=2,dst=6,val=28 -numa dist,src=3,dst=0,val=21 -numa dist,src=3,dst=1,val=31 -numa dist,src=3,dst=2,val=21 -numa dist,src=3,dst=3,val=10 -numa dist,src=3,dst=4,val=28 -numa dist,src=3,dst=5,val=28 -numa dist,src=3,dst=6,val=17 -numa dist,src=4,dst=0,val=17 -numa dist,src=4,dst=1,val=28 -numa dist,src=4,dst=2,val=28 -numa dist,src=4,dst=3,val=28 -numa dist,src=4,dst=4,val=10 -numa dist,src=4,dst=5,val=28 -numa dist,src=4,dst=6,val=28 -numa dist,src=5,dst=0,val=38 -numa dist,src=5,dst=1,val=17 -numa dist,src=5,dst=2,val=28 -numa dist,src=5,dst=3,val=28 -numa dist,src=5,dst=4,val=28 -numa dist,src=5,dst=5,val=10 -numa dist,src=5,dst=6,val=28 -numa dist,src=6,dst=0,val=38 -numa dist,src=6,dst=1,val=28 -numa dist,src=6,dst=2,val=28 -numa dist,src=6,dst=3,val=17 -numa dist,src=6,dst=4,val=28 -numa dist,src=6,dst=5,val=28 -numa dist,src=6,dst=6,val=10 -smp 16,sockets=4,dies=1,cores=4,threads=1 -fsdev local,security_model=passthrough,id=fsdev0,path=/home/mysuser/share -device virtio-9p-pci,id=fs0,fsdev=fsdev0,mount_tag=share_host -daemonize output from numactl -H: $ numactl -H available: 7 nodes (0-6) node 0 cpus: 0 1 2 3 node 0 size: 250 MB node 0 free: 191 MB node 1 cpus: 4 5 6 7 node 1 size: 251 MB node 1 free: 199 MB node 2 cpus: 8 9 10 11 node 2 size: 251 MB node 2 free: 218 MB node 3 cpus: 12 13 14 15 node 3 size: 251 MB node 3 free: 118 MB node 4 cpus: node 4 size: 1511 MB node 4 free: 1507 MB node 5 cpus: node 5 size: 1447 MB node 5 free: 1443 MB node 6 cpus: node 6 size: 1489 MB node 6 free: 1484 MB node distances: node 0 1 2 3 4 5 6 0: 10 21 31 21 17 38 28 1: 21 10 21 31 28 17 38 2: 31 21 10 21 28 28 28 3: 21 31 21 10 28 28 17 4: 17 28 28 28 10 28 28 5: 38 17 28 28 28 10 28 6: 38 28 28 17 28 28 10 To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1912170/+subscriptions