"live-restore" allows starting a VM immediately from a backup snapshot, no
waiting for a long restore process. This is made possible with QEMU backing
images, i.e. data is read from the backup which is attached to the VM as a
drive, but new data is written to the destination, while a background process
('block-stream') copies over data in a linear fashion as well.QEMU backing images are normally only supported for qcow2 images, but since the destination always starts out empty, we can use a dirty bitmap to achieve the same effect - this is implemented as the 'alloc-track' driver in the 'qemu' part of the series. The Rust part of the equation is adjusted to provide (quiet a lot) more caching, as mixing random read/write from the guest with the linear reads from the background process (both of which may use read sizes smaller or bigger than a single chunk) would thrash performance without large buffers. I've marked the feature as 'experimental' in the GUI for now, as I'm sure there are a lot of edge cases I've missed to test, and there's also the possibility of data loss, since anything the VM writes during the restore is removed if the restore fails. qemu: Stefan Reiter (3): PVE: explicitly add libuuid as linking dependency PVE: block/pbs: fast-path reads without allocation if possible block: add alloc-track driver Makefile.objs | 2 + block/Makefile.objs | 1 + block/alloc-track.c | 319 ++++++++++++++++++++++++++++++++++++++++++++ block/pbs.c | 17 ++- 4 files changed, 336 insertions(+), 3 deletions(-) create mode 100644 block/alloc-track.c proxmox-backup: Stefan Reiter (1): RemoteChunkReader: add LRU cached variant src/bin/proxmox_backup_client/mount.rs | 4 +- src/client/remote_chunk_reader.rs | 77 ++++++++++++++++++++------ 2 files changed, 62 insertions(+), 19 deletions(-) proxmox-backup-qemu: Stefan Reiter (1): access: use bigger cache and LRU chunk reader src/restore.rs | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) qemu-server: Stefan Reiter (5): make qemu_drive_mirror_monitor more generic cfg2cmd: allow PBS snapshots as backing files for drives enable live-restore for PBS extract register_qmeventd_handle to QemuServer.pm live-restore: register qmeventd handle PVE/API2/Qemu.pm | 15 ++- PVE/QemuServer.pm | 263 ++++++++++++++++++++++++++++++++------- PVE/VZDump/QemuServer.pm | 32 +---- 3 files changed, 233 insertions(+), 77 deletions(-) manager: Stefan Reiter (1): ui: restore: add live-restore checkbox www/manager6/grid/BackupView.js | 8 +++++-- www/manager6/storage/BackupView.js | 7 ++++-- www/manager6/window/Restore.js | 38 +++++++++++++++++++++++++++++- 3 files changed, 48 insertions(+), 5 deletions(-) -- 2.20.1 _______________________________________________ pve-devel mailing list [email protected] https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel
