* feat(backends/s3): add warmup support before repacks and restores
This commit introduces basic support for transitioning pack files stored
in cold storage to hot storage on S3 and S3-compatible providers.
To prevent unexpected behavior for existing users, the feature is gated
behind new flags:
- `s3.enable-restore`: opt-in flag (defaults to false)
- `s3.restore-days`: number of days for the restored objects to remain
in hot storage (defaults to `7`)
- `s3.restore-timeout`: maximum time to wait for a single restoration
(default to `1 day`)
- `s3.restore-tier`: retrieval tier at which the restore will be
processed. (default to `Standard`)
As restoration times can be lengthy, this implementation preemptively
restores selected packs to prevent incessant restore-delays during
downloads. This is slightly sub-optimal as we could process packs
out-of-order (as soon as they're transitioned), but this would really
add too much complexity for a marginal gain in speed.
To maintain simplicity and prevent resources exhautions with lots of
packs, no new concurrency mechanisms or goroutines were added. This just
hooks gracefully into the existing routines.
**Limitations:**
- Tests against the backend were not written due to the lack of cold
storage class support in MinIO. Testing was done manually on
Scaleway's S3-compatible object storage. If necessary, we could
explore testing with LocalStack or mocks, though this requires further
discussion.
- Currently, this feature only warms up before restores and repacks
(prune/copy), as those are the two main use-cases I came across.
Support for other commands may be added in future iterations, as long
as affected packs can be calculated in advance.
- The feature is gated behind a new alpha `s3-restore` feature flag to
make it explicit that the feature is still wet behind the ears.
- There is no explicit user notification for ongoing pack restorations.
While I think it is not necessary because of the opt-in flag, showing
some notice may improve usability (but would probably require major
refactoring in the progress bar which I didn't want to start). Another
possibility would be to add a flag to send restores requests and fail
early.
See https://github.com/restic/restic/issues/3202
* ui: warn user when files are warming up from cold storage
* refactor: remove the PacksWarmer struct
It's easier to handle multiple handles in the backend directly, and it
may open the door to reducing the number of requests made to the backend
in the future.
The new functions much better convey the intent behind the lock
request. This allows cleanly integrating noLock (for read) and dryRun
(write/exclusive) handling.
There are only minor changes to existing behavior with two exceptions:
- `tag` no longer accepts the `--no-lock` flag. As it replaces files in
the repository, this always requires an exclusive lock.
- `debug examine` now returns an error if both `--extract-pack` and
`--no-lock` are given.
This change better resembles the output generated by `Snapshot.String()`,
which includes both username and hostname.
Closes#4506
Before:
```
$ restic copy --from-repo /srv/restic-repo
repository 3666882b opened (version 2, compression level auto)
repository 0085c387 opened (version 2, compression level auto)
created new cache in /home/mike/.cache/restic
[0:00] 100.00% 1 / 1 index files loaded
[0:00] 0 index files loaded
snapshot 32b39a20 of [/home/mike/data] at 2023-10-21 16:01:13.979948154 -0300 -03)
copy started, this may take a while...
[0:00] 100.00% 1 / 1 packs copied
snapshot 10331fdd saved
```
After:
```
$ restic copy --from-repo /srv/restic-repo
repository 3666882b opened (version 2, compression level auto)
repository 0085c387 opened (version 2, compression level auto)
[0:00] 100.00% 1 / 1 index files loaded
[0:00] 0 index files loaded
snapshot 32b39a20 of [/home/mike/data] at 2023-10-21 16:01:13.979948154 -0300 -03 by mike@desktop)
copy started, this may take a while...
[0:00] 100.00% 1 / 1 packs copied
snapshot a67bd1ee saved
```
As the `Fatal` error type only includes a string, it becomes impossible
to inspect the contained error. This is for a example a problem for the
fuse implementation, which must be able to detect context.Canceled
errors.
Co-authored-by: greatroar <61184462+greatroar@users.noreply.github.com>
Fixes restic#719
If the option is passed, restic will wait the specified duration of time
and retry locking the repo every 10 seconds (or more often if the total
timeout is relatively small).
- Play nice with json output
- Reduce wait time in lock tests
- Rework timeout last attempt
- Reduce test wait time to 0.1s
- Use exponential back off for the retry lock
- Don't pass gopts to lockRepo functions
- Use global variable for retry sleep setup
- Exit retry lock on cancel
- Better wording for flag help
- Reorder debug statement
- Refactor tests
- Lower max sleep time to 1m
- Test that we cancel/timeout in time
- Use non blocking sleep function
- Refactor into minDuration func
Co-authored-by: Julian Brost <julian@0x4a42.net>
This turns snapshotFilterOptions from cmd into a restic.SnapshotFilter
type and makes restic.FindFilteredSnapshot and FindFilteredSnapshots
methods on that type. This fixes#4211 by ensuring that hosts and paths
are named struct fields instead of unnamed function arguments in long
lists of such.
Timestamp limits are also included in the new type. To avoid too much
pointer handling, the convention is that time zero means no limit.
That's January 1st, year 1, 00:00 UTC, which is so unlikely a date that
we can sacrifice it for simpler code.
Previously the global context was either accessed via gopts.ctx,
stored in a local variable and then used within that function or
sometimes both. This makes it very hard to follow which ctx or a wrapped
version of it reaches which method.
Thus just drop the context from the globalOptions struct and pass it
explicitly to every command line handler method.
`init` and `copy` use `--repo2` with two different meaning which has
proven to be confusing for users. `--from-repo` now consistently marks a
source repository from which data is read. `--repo` is now always the
target/destination repository.
These commands filter the snapshots according to some criteria which
essentially requires loading the index before filtering the snapshots.
Thus create a copy of the snapshots list beforehand and use it later on.
The repack operation copies all selected blobs from a set of pack files
into new pack files. For prune the source and destination repositories
are identical. To implement copy, just use a different source and
destination repository.
Currently restic copy will copy each blob from every snapshot serially,
which has performance implications on high-latency backends such as b2.
This commit introduces 8x parallelism for blob downloads/uploads which
can improve restic copy operations up to 8x for repositories with many
small blobs on b2.
This commit also addresses the TODO comment in the copyTree function.
Related work:
A more thorough improvement of the restic copy performance can be found
in PR #3513
This avoids problems when for some reason the JSON encoding changes.
This also ensures forward compatibility with future restic versions
which might e.g. add new fields to the tree metadata.
This assigns an id to each tree root and then keeps track of how many
tree loads (i.e. trees referenced for the first time) are pending per
tree root. Once a tree root and its subtrees were fully processed there
are no more pending tree loads and the tree root is reported as
processed.
This allows creating multiple repositories with identical chunker
parameters which is required for working deduplication when copying
snapshots between different repositories.