#### Problem
Snapshot names are overloaded, and there are multiple terms that mean the same thing. This is confusing. Here's a list of ones in the codebase that I've found:
```
- snapshot_dir
- snapshots_dir
- snapshot_path
- snapshot_output_dir
- snapshot_package_output_path
- snapshot_archives_dir
```
#### Summary of Changes
For all the ones that are about the directory where snapshot archives are stored, ensure they are `snapshot_archives_dir`. For the ones about the (bank) snapshots directory, set to `bank_snapshots_dir`.
Co-authored-by: Michael Vines <mvines@gmail.com>
While reviewing PR #18565, as issue was brought up to refactor some code
around verifying the bank after rebuilding from snapshots. A new
top-level function has been added to get the latest snapshot archives
and load the bank then verify. Additionally, new tests have been
written and existing tests have been updated to use this new function.
Fixes#18973
While resolving the issue, it became clear there was some additional
low-hanging fruit this change enabled. Specifically, the functions
`bank_to_xxx_snapshot_archive()` now return their respective
`SnapshotArchiveInfo`. And on the flip side,
`bank_from_snapshot_archives()` now takes `SnapshotArchiveInfo`s instead
of separate paths and archive formats. This bundling simplifies bank
rebuilding.
This commit also renames `snapshot_interval_slots` to
`full_snapshot_archive_interval_slots`, updates the comments on the
fields, and make appropriate updates where SnapshotConfig is used.
This commit adds high-level functions for creating and loading-from
incremental snapshots, plus all low-level functions required to perform
those tasks. This commit **does not** add taking incremental snapshots
as part of a running validator, nor starting up a node with an
incremental snapshot; just laying ground work.
Additionally, `snapshot_utils` and `serde_snapshot` have been
refactored to use a common code paths for the different snapshots.
Also of note, some renaming has happened:
1. Snapshots are now either `full_` or `incremental_` throughout the
codebase. If not specified, the code applies to both.
2. Bank snapshots now are called "bank snapshots"
(before they were called "slot snapshots", "bank snapshots", or
just "snapshots"). The one exception is within `Bank`, where they
are still just "snapshots", because they are already "bank
snapshots".
3. Snapshot archives now have `_archive` in the code. This
should clear up an ambiguity between bank snapshots and snapshot
archives.
Convert to use type alias for the callback and cascade the changes to callers. Thanks @jeffwashington for the help making it possible.
Changed the closure for the progress update in the validator main to FnMut and modify the abort count in the closure which is more reliable.
* Move gossip modules to solana-gossip
* Update Protocol abi digest due to move
* Move gossip benches and hook up CI
* Remove unneeded Result entries
* Single use statements
1. Allow the validator bootstrap code to specify the minimal snapshot download speed. If the snapshot download speed is detected below that, a different RPC can be retried. The default is 10MB/sec.
2. To prevent spinning on a number of sub-optimal choices and not making progress, the abort/retry logic is implemented with the following safe guards:
2.1 at maximum we do this retry for 5 times -- this number is configurable with default 5.
2.2 if the download in one notification round (5 second) is more than 2%, do not do retry -- it is not as bad anyway.
2.3 if the remaining estimate time is less than 1 minutes, do not abort retry as it will be done quickly anyway.
2.4 We do this abort/retry logic only at the first notification to avoid wasting download efforts -- the reasoning is being opportunistic and too greedy may not achieve overall shorter download time.
3. The download_snapshot and download_file is modified with the option allowing caller to notified of download progress via a callback. This allows the business logic of retrying to the place it belongs.
