09.07.2020 16:26, Denis V. Lunev wrote:
This patch creates intermediate buffer for reading from block driver state and performs read-ahead to this buffer. Snapshot code performs reads sequentially and thus we know what offsets will be required and when they will become not needed.Results are fantastic. Switch to snapshot times of 2GB Fedora 31 VM over NVME storage are the following: original fixed cached: 1.84s 1.16s non-cached: 12.74s 1.27s The difference over HDD would be more significant:) Signed-off-by: Denis V. Lunev<[email protected]> CC: Vladimir Sementsov-Ogievskiy<[email protected]> CC: Kevin Wolf<[email protected]> CC: Max Reitz<[email protected]> CC: Stefan Hajnoczi<[email protected]> CC: Fam Zheng<[email protected]> CC: Juan Quintela<[email protected]> CC: Denis Plotnikov<[email protected]>
Reviewed-by: Vladimir Sementsov-Ogievskiy <[email protected]> -- Best regards, Vladimir
