Dominik Csapak e0fb53e41d datastore: implement sync-level tuning for datastores ... currently, we don't (f)sync on chunk insertion (or at any point after that), which can lead to broken chunks in case of e.g. an unexpected powerloss. To fix that, offer a tuning option for datastores that controls the level of syncs it does: * None (default): same as current state, no (f)syncs done at any point * Filesystem: at the end of a backup, the datastore issues a syncfs(2) to the filesystem of the datastore * File: issues an fsync on each chunk as they get inserted (using our 'replace_file' helper) and a fsync on the directory handle a small benchmark showed the following (times in mm:ss): setup: virtual pbs, 4 cores, 8GiB memory, ext4 on spinner size none filesystem file 2GiB (fits in ram) 00:13 0:41 01:00 33GiB 05:21 05:31 13:45 so if the backup fits in memory, there is a large difference between all of the modes (expected), but as soon as it exceeds the memory size, the difference between not syncing and syncing the fs at the end becomes much smaller. i also tested on an nvme, but there the syncs basically made no difference Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>		2022-10-20 14:59:15 +02:00
..
src	datastore: implement sync-level tuning for datastores	2022-10-20 14:59:15 +02:00
Cargo.toml	api-types: add BackupNamespace type	2022-05-12 09:33:50 +02:00