Re: [libvirt] Error when creating VM with persistent memory
On 9/4/19 6:31 PM, Dan Williams wrote: > On Wed, Sep 4, 2019 at 12:56 AM Seema Pandit wrote: >> >> Actually there is still some issue around this. When trying to start another >> VM, so using even more pmem, there is a different issue now. Error copied >> below. >> >> []# virsh start manual_clone >> >> error: Failed to start domain manual_clone >> >> error: internal error: qemu unexpectedly closed the monitor: ftruncate: >> Invalid argument >> >> 2019-09-03T21:28:41.031924Z qemu-system-x86_64: -object >> memory-backend-file,id=memnvdimm0,prealloc=yes,mem-path=/dev/dax1.1,share=yes,size=7301032: >> os_mem_prealloc: Insufficient free host memory pages available to allocate >> guest RAM > > /dev/dax instances do not support the ftruncate syscall, and > device-dax instances are already fully allocated by definition. The > prealloc option is simply invalid for /dev/dax targets. Ah, in that case we need an XML knob that if set doesn't put prealloc=yes onto the qemu cmd line. Unfortunatelly, I don't think I have any spare time to implement that, so please be my guest. Michal -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
Re: [libvirt] Error when creating VM with persistent memory
On Wed, Sep 4, 2019 at 12:56 AM Seema Pandit wrote: > > Actually there is still some issue around this. When trying to start another > VM, so using even more pmem, there is a different issue now. Error copied > below. > > []# virsh start manual_clone > > error: Failed to start domain manual_clone > > error: internal error: qemu unexpectedly closed the monitor: ftruncate: > Invalid argument > > 2019-09-03T21:28:41.031924Z qemu-system-x86_64: -object > memory-backend-file,id=memnvdimm0,prealloc=yes,mem-path=/dev/dax1.1,share=yes,size=7301032: > os_mem_prealloc: Insufficient free host memory pages available to allocate > guest RAM /dev/dax instances do not support the ftruncate syscall, and device-dax instances are already fully allocated by definition. The prealloc option is simply invalid for /dev/dax targets. -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
Re: [libvirt] Error when creating VM with persistent memory
On Mon, Sep 2, 2019 at 10:10 AM Seema Pandit wrote: > > After adding the memoryBacking tag in xml as below (in addition, to other xml > changes to add nvdimm), virsh could allocate AD memory larger than the system > RAM and VMs could start successfully. > > > > > > > > > > > > This adds share=yes in command line. > > > > -object > memory-backend-file,id=memnvdimm0,prealloc=yes,mem-path=/mnt/pmem0/file1,share=yes,size=414464344064 > -device nvdimm,node=0,label-size=131072,memdev=memnvdimm0,id=nvdimm0,slot=0 > > > > > > For reference qemu command line where VM starts quickly: > > qemu-system-x86_64 \ > > -name qemu-gold29 \ > > -drive > file=/var/lib/libvirt/images/gold29-ad.qcow2,format=qcow2,index=0,media=disk > \ -m 2G,slots=4,maxmem=428G \ -smp 2 \ -machine pc,accel=kvm,nvdimm=on \ > -enable-kvm \ -object > memory-backend-file,id=pmem1,share=on,mem-path=/mnt/pmem0/file1,size=386G,align=4K > \ -device nvdimm,memdev=pmem1,id=nv1 \ -daemonize > > > > > > Qemu command line generated from virsh: (please note VM now starts with this > command line, shared=yes.) > > > > /usr/bin/qemu-system-x86_64 -machine accel=kvm -name > guest=mix-test,debug-threads=on -S -object > secret,id=masterKey0,format=raw,file=/var/lib/libvirt/qemu/domain-18-mix-test/master-key.aes > -machine > pc-i440fx-3.0,accel=kvm,usb=off,vmport=off,dump-guest-core=off,nvdimm=on -cpu > Skylake-Server-IBRS,hypervisor=on -m size=2097152k,slots=16,maxmem=419430400k > -realtime mlock=off -smp 2,sockets=2,cores=1,threads=1 -object > memory-backend-file,id=ram-node0,mem-path=/var/lib/libvirt/qem > /ram/libvirt/qemu/18-mix-test/ram-node0,discard-data=yes,share=yes,size=2147483648 > -numa node,nodeid=0,cpus=0-1,memdev=ram-node0 -object > memory-backend-file,id=memnvdimm0,prealloc=yes,mem-path=/mnt/pmem0/file1,share=yes,size=414464344064 > -device nvdimm,node=0,label-size=131072,memdev=memnvdimm0,id=nvdimm0,slot=0 > -uuid 318c0529-0330-460b-8d0a-3b253e9decdd -no-user-config -nodefaults > -chardev socket,id=charmonitor,fd=32,server,nowait -mon > chardev=charmonitor,id=monitor,mode=control -rtc base=utc,driftfix=slew -g lobal kvm-pit.lost_tick_policy=delay -no-hpet -no-shutdown -global PIIX4_PM.disable_s3=1 -global PIIX4_PM.disable_s4=1 -boot strict=on -device ich9-usb-ehci1,id=usb,bus=pci.0,addr=0x5.0x7 -device ich9-usb-uhci1,masterbus=usb.0,firstport=0,bus=pci.0,multifunction=on,addr=0x5 -device ich9-usb-uhci2,masterbus=usb.0,firstport=2,bus=pci.0,addr=0x5.0x1 -device ich9-usb-uhci3,masterbus=usb.0,firstport=4,bus=pci.0,addr=0x5.0x2 -device virtio-serial-pci,id=virtio-serial0,bus=pci.0,addr=0x6 -drive file=/var/lib/libvirt/images/mix-test.qcow2,format=qcow2,if=none,id=drive-virtio-disk0 -device virtio-blk-pci,scsi=off,bus=pci.0,addr=0x7,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1 -drive if=none,id=drive-ide0-0-0,readonly=on -device ide-cd,bus=ide.0,unit=0,drive=drive-ide0-0-0,id=ide0-0-0 -netdev tap,fd=34,id=hostnet0 -device e1000,netdev=hostnet0,id=net0,mac=52:54:00:06:db:55,bus=pci.0,addr=0xa -chardev pty,id=charserial0 -device isa-serial,chardev=charserial0,id=serial0 -chardev socket, id=charchannel0,fd=35,server,nowait -device virtserialport,bus=virtio-serial0.0,nr=1,chardev=charchannel0,id=channel0,name=org.qemu.guest_agent.0 -chardev spicevmc,id=charchannel1,name=vdagent -device virtserialport,bus=virtio-serial0.0,nr=2,chardev=charchannel1,id=channel1,name=com.redhat.spice.0 -device usb-tablet,id=input0,bus=usb.0,port=1 -spice port=5901,addr=127.0.0.1,disable-ticketing,image-compression=off,seamless-migration=on -device qxl-vga,id=video0,ram_size=67108864,vram_size=67108864,vram64_size_mb=0,vgamem_mb=16,max_outputs=1,bus=pci.0,addr=0x2 -device intel-hda,id=sound0,bus=pci.0,addr=0x4 -device hda-duplex,id=sound0-codec0,bus=sound0.0,cad=0 -chardev spicevmc,id=charredir0,name=usbredir -device usb-redir,chardev=charredir0,id=redir0,bus=usb.0,port=2 -chardev spicevmc,id=charredir1,name=usbredir -device usb-redir,chardev=charredir1,id=redir1,bus=usb.0,port=3 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x8 -object rng-random,id=objrng0,filename=/dev/urandom -device virtio-rng-pci,rng=objrng0,id=rng0,bus=pci.0,addr=0x9 -sandbox on,obsolete=deny,elevateprivileges=deny,spawn=deny,resourcecontrol=deny -msg timestamp=on > > > VM start takes longer that qemu. Any thoughts?? Why is prealloc=yes default > on for nvdimm? Any other important deltas? > The "prealloc" option is a "pay me now" vs "pay me later" type of decision. If the guest workload is ok to absorb fault latency at run time then disable prealloc, if it would prefer more predictable latency and pay all the fault penalty up front then specify prealloc. The "shared" parameter, if it means MAP_SHARED vs MAP_PRIVATE, must be set to "yes" if the guest expects persistence. MAP_PRIVATE is otherwise unacceptable for emulating persistent memory because writes to private memory are discarded, and as you have seen
Re: [libvirt] Error when creating VM with persistent memory
Actually there is still some issue around this. When trying to start another VM, so using even more pmem, there is a different issue now. Error copied below. []# virsh start manual_clone error: Failed to start domain manual_clone error: internal error: qemu unexpectedly closed the monitor: ftruncate: Invalid argument 2019-09-03T21:28:41.031924Z qemu-system-x86_64: -object memory-backend-file,id=memnvdimm0,prealloc=yes,mem-path=/dev/dax1.1,share=yes,size=7301032: os_mem_prealloc: Insufficient free host memory pages available to allocate guest RAM Old error was Error: # virsh start test error: Failed to start domain test error: internal error: qemu unexpectedly closed the monitor: ftruncate: Invalid argument 2019-08-22T04:16:08.744402Z qemu-system-x86_64: -object memory-backend-file,id=memnvdimm0,prealloc=yes,mem-path=/dev/dax1.0,size=403726925824: unable to map backing store for guest RAM: Cannot allocate memory On Tue, Sep 3, 2019 at 9:53 AM Dan Williams wrote: > On Mon, Sep 2, 2019 at 10:10 AM Seema Pandit wrote: > > > > After adding the memoryBacking tag in xml as below (in addition, to > other xml changes to add nvdimm), virsh could allocate AD memory larger > than the system RAM and VMs could start successfully. > > > > > > > > > > > > > > > > > > > > > > > > This adds share=yes in command line. > > > > > > > > -object > memory-backend-file,id=memnvdimm0,prealloc=yes,mem-path=/mnt/pmem0/file1,share=yes,size=414464344064 > -device nvdimm,node=0,label-size=131072,memdev=memnvdimm0,id=nvdimm0,slot=0 > > > > > > > > > > > > For reference qemu command line where VM starts quickly: > > > > qemu-system-x86_64 \ > > > > -name qemu-gold29 \ > > > > -drive > file=/var/lib/libvirt/images/gold29-ad.qcow2,format=qcow2,index=0,media=disk > \ -m 2G,slots=4,maxmem=428G \ -smp 2 \ -machine pc,accel=kvm,nvdimm=on \ > -enable-kvm \ -object > memory-backend-file,id=pmem1,share=on,mem-path=/mnt/pmem0/file1,size=386G,align=4K > \ -device nvdimm,memdev=pmem1,id=nv1 \ -daemonize > > > > > > > > > > > > Qemu command line generated from virsh: (please note VM now starts with > this command line, shared=yes.) > > > > > > > > /usr/bin/qemu-system-x86_64 -machine accel=kvm -name > guest=mix-test,debug-threads=on -S -object > secret,id=masterKey0,format=raw,file=/var/lib/libvirt/qemu/domain-18-mix-test/master-key.aes > -machine > pc-i440fx-3.0,accel=kvm,usb=off,vmport=off,dump-guest-core=off,nvdimm=on > -cpu Skylake-Server-IBRS,hypervisor=on -m > size=2097152k,slots=16,maxmem=419430400k -realtime mlock=off -smp > 2,sockets=2,cores=1,threads=1 -object > memory-backend-file,id=ram-node0,mem-path=/var/lib/libvirt/qem > /ram/libvirt/qemu/18-mix-test/ram-node0,discard-data=yes,share=yes,size=2147483648 > -numa node,nodeid=0,cpus=0-1,memdev=ram-node0 -object > memory-backend-file,id=memnvdimm0,prealloc=yes,mem-path=/mnt/pmem0/file1,share=yes,size=414464344064 > -device nvdimm,node=0,label-size=131072,memdev=memnvdimm0,id=nvdimm0,slot=0 > -uuid 318c0529-0330-460b-8d0a-3b253e9decdd -no-user-config -nodefaults > -chardev socket,id=charmonitor,fd=32,server,nowait -mon > chardev=charmonitor,id=monitor,mode=control -rtc base=utc,driftfix=slew > -global kvm-pit.lost_tick_policy=delay -no-hpet -no-shutdown -global > PIIX4_PM.disable_s3=1 -global PIIX4_PM.disable_s4=1 -boot strict=on -device > ich9-usb-ehci1,id=usb,bus=pci.0,addr=0x5.0x7 -device > ich9-usb-uhci1,masterbus=usb.0,firstport=0,bus=pci.0,multifunction=on,addr=0x5 > -device ich9-usb-uhci2,masterbus=usb.0,firstport=2,bus=pci.0,addr=0x5.0x1 > -device ich9-usb-uhci3,masterbus=usb.0,firstport=4,bus=pci.0,addr=0x5.0x2 > -device virtio-serial-pci,id=virtio-serial0,bus=pci.0,addr=0x6 -drive > file=/var/lib/libvirt/images/mix-test.qcow2,format=qcow2,if=none,id=drive-virtio-disk0 > -device > virtio-blk-pci,scsi=off,bus=pci.0,addr=0x7,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1 > -drive if=none,id=drive-ide0-0-0,readonly=on -device > ide-cd,bus=ide.0,unit=0,drive=drive-ide0-0-0,id=ide0-0-0 -netdev > tap,fd=34,id=hostnet0 -device > e1000,netdev=hostnet0,id=net0,mac=52:54:00:06:db:55,bus=pci.0,addr=0xa > -chardev pty,id=charserial0 -device > isa-serial,chardev=charserial0,id=serial0 -chardev > socket,id=charchannel0,fd=35,server,nowait -device > virtserialport,bus=virtio-serial0.0,nr=1,chardev=charchannel0,id=channel0,name=org.qemu.guest_agent.0 > -chardev spicevmc,id=charchannel1,name=vdagent -device > virtserialport,bus=virtio-serial0.0,nr=2,chardev=charchannel1,id=channel1,name=com.redhat.spice.0 > -device usb-tablet,id=input0,bus=usb.0,port=1 -spice > port=5901,addr=127.0.0.1,disable-ticketing,image-compression=off,seamless-migration=on > -device > qxl-vga,id=video0,ram_size=67108864,vram_size=67108864,vram64_size_mb=0,vgamem_mb=16,max_outputs=1,bus=pci.0,addr=0x2 > -device intel-hda,id=sound0,bus=pci.0,addr=0x4 -device > hda-duplex,id=sound0-codec0,bus=sound0.0,cad=0 -chardev > spicevmc,id=charredir0,name=usbredir -device >
Re: [libvirt] Error when creating VM with persistent memory
After adding the memoryBacking tag in xml as below (in addition, to other xml changes to add nvdimm), virsh could allocate AD memory larger than the system RAM and VMs could start successfully. This adds share=yes in command line. -object memory-backend-file,id=memnvdimm0,prealloc=yes,mem-path=/mnt/pmem0/file1,share=yes,size=414464344064 -device nvdimm,node=0,label-size=131072,memdev=memnvdimm0,id=nvdimm0,slot=0 For reference qemu command line where VM starts quickly: qemu-system-x86_64 \ -name qemu-gold29 \ -drive file=/var/lib/libvirt/images/gold29-ad.qcow2,format=qcow2,index=0,media=disk \ -m 2G,slots=4,maxmem=428G \ -smp 2 \ -machine pc,accel=kvm,nvdimm=on \ -enable-kvm \ -object memory-backend-file,id=pmem1,share=on,mem-path=/mnt/pmem0/file1,size=386G,align=4K \ -device nvdimm,memdev=pmem1,id=nv1 \ -daemonize Qemu command line generated from virsh: (please note VM now starts with this command line, shared=yes.) /usr/bin/qemu-system-x86_64 -machine accel=kvm -name guest=mix-test,debug-threads=on -S -object secret,id=masterKey0,format=raw,file=/var/lib/libvirt/qemu/domain-18-mix-test/master-key.aes -machine pc-i440fx-3.0,accel=kvm,usb=off,vmport=off,dump-guest-core=off,nvdimm=on -cpu Skylake-Server-IBRS,hypervisor=on -m size=2097152k,slots=16,maxmem=419430400k -realtime mlock=off -smp 2,sockets=2,cores=1,threads=1 -object memory-backend-file,id=ram-node0,mem-path=/var/lib/libvirt/qem /ram/libvirt/qemu/18-mix-test/ram-node0,discard-data=yes,share=yes,size=2147483648 -numa node,nodeid=0,cpus=0-1,memdev=ram-node0 -object memory-backend-file,id=memnvdimm0,prealloc=yes,mem-path=/mnt/pmem0/file1,share=yes,size=414464344064 -device nvdimm,node=0,label-size=131072,memdev=memnvdimm0,id=nvdimm0,slot=0 -uuid 318c0529-0330-460b-8d0a-3b253e9decdd -no-user-config -nodefaults -chardev socket,id=charmonitor,fd=32,server,nowait -mon chardev=charmonitor,id=monitor,mode=control -rtc base=utc,driftfix=slew -global kvm-pit.lost_tick_policy=delay -no-hpet -no-shutdown -global PIIX4_PM.disable_s3=1 -global PIIX4_PM.disable_s4=1 -boot strict=on -device ich9-usb-ehci1,id=usb,bus=pci.0,addr=0x5.0x7 -device ich9-usb-uhci1,masterbus=usb.0,firstport=0,bus=pci.0,multifunction=on,addr=0x5 -device ich9-usb-uhci2,masterbus=usb.0,firstport=2,bus=pci.0,addr=0x5.0x1 -device ich9-usb-uhci3,masterbus=usb.0,firstport=4,bus=pci.0,addr=0x5.0x2 -device virtio-serial-pci,id=virtio-serial0,bus=pci.0,addr=0x6 -drive file=/var/lib/libvirt/images/mix-test.qcow2,format=qcow2,if=none,id=drive-virtio-disk0 -device virtio-blk-pci,scsi=off,bus=pci.0,addr=0x7,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1 -drive if=none,id=drive-ide0-0-0,readonly=on -device ide-cd,bus=ide.0,unit=0,drive=drive-ide0-0-0,id=ide0-0-0 -netdev tap,fd=34,id=hostnet0 -device e1000,netdev=hostnet0,id=net0,mac=52:54:00:06:db:55,bus=pci.0,addr=0xa -chardev pty,id=charserial0 -device isa-serial,chardev=charserial0,id=serial0 -chardev socket,id=charchannel0,fd=35,server,nowait -device virtserialport,bus=virtio-serial0.0,nr=1,chardev=charchannel0,id=channel0,name=org.qemu.guest_agent.0 -chardev spicevmc,id=charchannel1,name=vdagent -device virtserialport,bus=virtio-serial0.0,nr=2,chardev=charchannel1,id=channel1,name=com.redhat.spice.0 -device usb-tablet,id=input0,bus=usb.0,port=1 -spice port=5901,addr=127.0.0.1,disable-ticketing,image-compression=off,seamless-migration=on -device qxl-vga,id=video0,ram_size=67108864,vram_size=67108864,vram64_size_mb=0,vgamem_mb=16,max_outputs=1,bus=pci.0,addr=0x2 -device intel-hda,id=sound0,bus=pci.0,addr=0x4 -device hda-duplex,id=sound0-codec0,bus=sound0.0,cad=0 -chardev spicevmc,id=charredir0,name=usbredir -device usb-redir,chardev=charredir0,id=redir0,bus=usb.0,port=2 -chardev spicevmc,id=charredir1,name=usbredir -device usb-redir,chardev=charredir1,id=redir1,bus=usb.0,port=3 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x8 -object rng-random,id=objrng0,filename=/dev/urandom -device virtio-rng-pci,rng=objrng0,id=rng0,bus=pci.0,addr=0x9 -sandbox on,obsolete=deny,elevateprivileges=deny,spawn=deny,resourcecontrol=deny -msg timestamp=on VM start takes longer that qemu. Any thoughts?? Why is prealloc=yes default on for nvdimm? Any other important deltas? On Mon, Sep 2, 2019 at 12:21 PM Michal Privoznik wrote: > On 8/31/19 7:33 PM, Seema Pandit wrote: > > Hi Michal, > > Thank you for the reply. > > I was having issues compiling qemu code on fedora29. So instead of > dropping > > prealloc in virsh, tried adding prealloc=yes in qemu command line. > > prealloc=yes works. It does not lead to using more system memory when > using > > DAX. > > +Dan > > Here are the steps: > > > > ndctl create-namespace -t pmem -m fsdax --align=4k -s 400G > > > > mkfs.ext4 /dev/pmem0 > > > > mount -o dax /dev/pmem0 /mnt/pmem0 > > > > dd if=/dev/zero of=/mnt/pmem0/file1 bs=4k count=104857600 > > > > [root@system-name]# dd if=/dev/zero of=/mnt/pmem0/file1 bs=4k > > count=104857600 > > > > dd: error writing
Re: [libvirt] Error when creating VM with persistent memory
On 8/31/19 7:33 PM, Seema Pandit wrote: Hi Michal, Thank you for the reply. I was having issues compiling qemu code on fedora29. So instead of dropping prealloc in virsh, tried adding prealloc=yes in qemu command line. prealloc=yes works. It does not lead to using more system memory when using DAX. +Dan Here are the steps: ndctl create-namespace -t pmem -m fsdax --align=4k -s 400G mkfs.ext4 /dev/pmem0 mount -o dax /dev/pmem0 /mnt/pmem0 dd if=/dev/zero of=/mnt/pmem0/file1 bs=4k count=104857600 [root@system-name]# dd if=/dev/zero of=/mnt/pmem0/file1 bs=4k count=104857600 dd: error writing '/mnt/pmem0/file1': No space left on device 101313980+0 records in 101313979+0 records out 414982057984 bytes (415 GB, 386 GiB) copied, 946.495 s, 438 MB/s Slightly smaller file is created than asked. [root@system-name]# du -sh 387G. sample qemu command line which works: qemu-system-x86_64 \ -name test \ -drive file=/var/lib/libvirt/images/test-ad.qcow2,format=qcow2,index=0,media=disk \ -m 2G,slots=4,maxmem=428G \ -smp 2 \ -machine pc,accel=kvm,nvdimm=on \ -enable-kvm \ -object memory-backend-file,id=pmem1,prealloc=yes,share=on,mem-path=/mnt/pmem0/file1,size=386G,align=4K \ -device nvdimm,memdev=pmem1,id=nv1 \ -daemonize Looks like the only difference to the cmd line generated by libvirt and this one then is align=4K. To confirm that, can you share the full qemu cmd line as generated by libvirt please? Libvirt does not do anything special with guest memory, so this is matter of qemu cmd line and that's why we need to see what's different, what works and what doesn't. Then we have some lead to understand the problem IMO. Michal -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
Re: [libvirt] Error when creating VM with persistent memory
Hi Michal, Thank you for the reply. I was having issues compiling qemu code on fedora29. So instead of dropping prealloc in virsh, tried adding prealloc=yes in qemu command line. prealloc=yes works. It does not lead to using more system memory when using DAX. +Dan Here are the steps: ndctl create-namespace -t pmem -m fsdax --align=4k -s 400G mkfs.ext4 /dev/pmem0 mount -o dax /dev/pmem0 /mnt/pmem0 dd if=/dev/zero of=/mnt/pmem0/file1 bs=4k count=104857600 [root@system-name]# dd if=/dev/zero of=/mnt/pmem0/file1 bs=4k count=104857600 dd: error writing '/mnt/pmem0/file1': No space left on device 101313980+0 records in 101313979+0 records out 414982057984 bytes (415 GB, 386 GiB) copied, 946.495 s, 438 MB/s Slightly smaller file is created than asked. [root@system-name]# du -sh 387G. sample qemu command line which works: qemu-system-x86_64 \ -name test \ -drive file=/var/lib/libvirt/images/test-ad.qcow2,format=qcow2,index=0,media=disk \ -m 2G,slots=4,maxmem=428G \ -smp 2 \ -machine pc,accel=kvm,nvdimm=on \ -enable-kvm \ -object memory-backend-file,id=pmem1,prealloc=yes,share=on,mem-path=/mnt/pmem0/file1,size=386G,align=4K \ -device nvdimm,memdev=pmem1,id=nv1 \ -daemonize So prealloc option works. But still passing /mnt/pmem0/file1 in virsh as the nvdimm fails to start the VM. Errors out saying cannot allocate that much memory. On Wed, Aug 28, 2019 at 6:49 PM Michal Privoznik wrote: > On 8/27/19 9:58 AM, Seema Pandit wrote: > > error: internal error: qemu unexpectedly closed the monitor: ftruncate: > > Invalid argument 2019-08-22T04:16:08.744402Z qemu-system-x86_64: -object > > > memory-backend-file,id=memnvdimm0,prealloc=yes,mem-path=/dev/dax1.0,size=403726925824: > > unable to map backing store for guest RAM: Cannot allocate memory > > I wonder if dropping 'prealloc' would help. This error message comes > from phase before 'prealloc' is processed. You can try the following > patch: > > > diff --git i/src/qemu/qemu_command.c w/src/qemu/qemu_command.c > index 373ebd6d1a..c375955eab 100644 > --- i/src/qemu/qemu_command.c > +++ w/src/qemu/qemu_command.c > @@ -3468,7 +3468,7 @@ qemuBuildMemoryBackendProps(virJSONValuePtr > *backendProps, > } > > if (virJSONValueObjectAdd(props, > - "B:prealloc", prealloc, > + "B:prealloc", prealloc ? false : false, >"s:mem-path", memPath, >NULL) < 0) > goto cleanup; > > Michal > -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
Re: [libvirt] Error when creating VM with persistent memory
On 8/27/19 9:58 AM, Seema Pandit wrote: > error: internal error: qemu unexpectedly closed the monitor: ftruncate: > Invalid argument 2019-08-22T04:16:08.744402Z qemu-system-x86_64: -object > memory-backend-file,id=memnvdimm0,prealloc=yes,mem-path=/dev/dax1.0,size=403726925824: > unable to map backing store for guest RAM: Cannot allocate memory I wonder if dropping 'prealloc' would help. This error message comes from phase before 'prealloc' is processed. You can try the following patch: diff --git i/src/qemu/qemu_command.c w/src/qemu/qemu_command.c index 373ebd6d1a..c375955eab 100644 --- i/src/qemu/qemu_command.c +++ w/src/qemu/qemu_command.c @@ -3468,7 +3468,7 @@ qemuBuildMemoryBackendProps(virJSONValuePtr *backendProps, } if (virJSONValueObjectAdd(props, - "B:prealloc", prealloc, + "B:prealloc", prealloc ? false : false, "s:mem-path", memPath, NULL) < 0) goto cleanup; Michal -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
