Christian Ebner cb9814e331 garbage collection: fix rare race in chunk marking phase ... During phase 1 of garbage collection referenced chunks are marked as in use by iterating over all index files and updating the atime on the chunks referenced by these. In an edge case for long running garbage collection jobs, where a newly added snapshot (created after the start of GC) reused known chunks from a previous snapshot, but the previous snapshot index referencing them disappeared before the marking phase could reach that index (e.g. pruned because only 1 snapshot to be kept by retention setting), known chunks from that previous index file might not be marked (given that by none of the other index files it was marked). Since commit 74361da8 ("garbage collection: generate index file list via datastore iterators") this is even less likely as now the iteration reads also index files added during phase 1, and therefore either the new or the previous index file will account for these chunks (the previous backup snapshot can only be pruned after the new one finished, since locked). There remains however a small race window between the reading of the snapshots in the backup group and the reading of the actual index files for marking. Fix this race by: 1. Checking if the last snapshot of a group disappeared and if so 2. generate the list again, looking for new index files previously not accounted for 3. To avoid possible endless looping, lock the group if the snapshot list changed even after the 10th time (which will lead to concurrent operations to this group failing). Signed-off-by: Christian Ebner <c.ebner@proxmox.com> Acked-by: Fabian Grünbichler <f.gruenbichler@proxmox.com> Link: https://lore.proxmox.com/20250416105000.270166-3-c.ebner@proxmox.com		2025-04-16 14:17:24 +02:00
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examples	pbs-datastore: clippy fixes	2023-05-17 17:43:17 +02:00
src	garbage collection: fix rare race in chunk marking phase	2025-04-16 14:17:24 +02:00
Cargo.toml	fix #3935: datastore/api/backup: move datastore locking to '/run'	2025-03-26 16:21:43 +01:00