kata-containers/cloud-hypervisor
1
0
Fork 0
mirror of https://github.com/cloud-hypervisor/cloud-hypervisor.git synced 2026-08-05 02:19:16 +00:00
Code Issues Packages Projects Releases Wiki Activity

block: raw: Implement disk preallocation for sparse=false

Browse Source 
When sparse=false is configured, preallocate the entire raw disk file
at startup using fallocate(). This provides space reservation and
reduces fragmentation.

Only applies to raw disks. QCOW2/VHD/VHDX formats manage their own
allocation.

Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
This commit is contained in:
Anatol Belski
2026-01-30 18:57:33 +01:00
committed by Rob Bradford
parent 0a287793df
commit 49a30cbbaf
2 changed files with 46 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

11
vmm/src/device_manager.rs
View File

@@ -39,7 +39,8 @@ use block::raw_async_aio::RawFileDiskAio;
use block::raw_sync::RawFileDiskSync;
use block::vhdx_sync::VhdxDiskSync;
use block::{
ImageType, block_aio_is_supported, block_io_uring_is_supported, detect_image_type, qcow, vhdx,
ImageType, block_aio_is_supported, block_io_uring_is_supported, detect_image_type,
preallocate_disk, qcow, vhdx,
};
#[cfg(feature = "io_uring")]
use block::{fixed_vhd_async::FixedVhdDiskAsync, raw_async::RawFileDisk};
@@ -2699,6 +2700,14 @@ impl DeviceManager {
}
}
ImageType::Raw => {
// For non-sparse RAW disks, preallocate disk space
if !disk_cfg.readonly
&& !disk_cfg.sparse
&& let Some(path) = &disk_cfg.path
{
preallocate_disk(&file, path);
}
// Use asynchronous backend relying on io_uring if the
// syscalls are supported.
if cfg!(feature = "io_uring")