Moka-py

Changed

- Make [Quanta crate][quanta-crate] optional (but enabled by default)
([121][gh-pull-0121])
- Quanta v0.9.3 or older may not work correctly on some x86_64 machines where
the Time Stamp Counter (TSC) is not synched across the processor cores.
([119][gh-issue-0119])
- This issue was fixed by Quanta v0.10.0. You can prevent the issue by upgrading
Moka to v0.8.4 or newer.
- For more details about the issue, see [the relevant section][panic_in_quanta]
of the README.

Added

- Add iterator to the following caches: ([114][gh-pull-0114])
- `sync::Cache`
- `sync::SegmentedCache`
- `future::Cache`
- `unsync::Cache`
- Implement `IntoIterator` to the all caches (including experimental `dash::Cache`)
([114][gh-pull-0114])

Fixed

- Fix the `dash::Cache` iterator not to return expired entries.
([116][gh-pull-0116])
- Prevent "index out of bounds" error when `sync::SegmentedCache` was created with
a non-power-of-two segments. ([117][gh-pull-0117])

Added

- Add `contains_key` method to check if a key is present without resetting the idle
timer or updating the historic popularity estimator. ([107][gh-issue-0107])

As a part of stabilizing the cache API, the following cache methods have been renamed:

- `get_or_insert_with(K, F)` → `get_with(K, F)`
- `get_or_try_insert_with(K, F)` → `try_get_with(K, F)`

Old methods are still available but marked as deprecated. They will be removed in a
future version.

Also `policy` method was added to all caches and `blocking` method was added to
`future::Cache`. They return a `Policy` struct or `BlockingOp` struct
respectively. Some uncommon cache methods were moved to these structs, and old
methods were removed without deprecating.

Please see [105][gh-pull-0105] for the complete list of the affected methods.

Changed

- API stabilization. (Smaller core cache API, shorter names for common methods)
([105][gh-pull-0105])
- Performance related:
- Improve performance of `get_with` and `try_get_with`. ([88][gh-pull-0088])
- Avoid to calculate the same hash twice in `get`, `get_with`, `insert`,
`invalidate`, etc. ([90][gh-pull-0090])
- Update the minimum versions of dependencies:
- crossbeam-channel to v0.5.4. ([100][gh-pull-0100])
- scheduled-thread-pool to v0.2.5. ([103][gh-pull-0103], by
[Milo123459][gh-Milo123459])
- (dev-dependency) skeptic to v0.13.5. ([104][gh-pull-0104])

Added

Experimental Additions

- Add a synchronous cache `moka::dash::Cache`, which uses `dashmap::DashMap` as the
internal storage. ([99][gh-pull-0099])
- Add iterator to `moka::dash::Cache`. ([101][gh-pull-0101])

Please note that the above additions are highly experimental and their APIs will
be frequently changed in next few releases.

The minimum supported Rust version (MSRV) is now 1.51.0 (Mar 25, 2021).

Fixed

- Addressed a memory utilization issue that will get worse when keys have hight
cardinality ([72][gh-issue-0072]):
- Reduce memory overhead in the internal concurrent hash table (cht).
([79][gh-pull-0079])
- Fix a bug that can create oversized frequency sketch when weigher is set.
([75][gh-pull-0075])
- Change `EntryInfo` from `enum` to `struct` to reduce memory utilization.
([76][gh-pull-0076])
- Replace some `std::sync::Arc` usages with `triomphe::Arc` to reduce memory
utilization. ([80][gh-pull-0080])
- Embed `CacheRegion` value into a 2-bit tag space of `TagNonNull` pointer.
([84][gh-pull-0084])
- Fix a bug that will use wrong (oversized) initial capacity for the internal cht.
([83][gh-pull-0083])

Added

- Add `unstable-debug-counters` feature for testing purpose. ([82][gh-pull-0082])

Changed

- Import (include) cht source files for better integration. ([77][gh-pull-0077],
[86](gh-pull-0086))
- Improve the CI coverage for Clippy lints and fix some Clippy warnings in unit
tests. ([73][gh-pull-0073], by [06chaynes][gh-06chaynes])

- **Important Fix**: A memory leak issue (65 below) was found in all previous
versions (since v0.1.0) and fixed in this version. All users are encouraged to
upgrade to this or newer version.

Fixed

- Fix a memory leak that will happen when evicting/expiring an entry or manually
invalidating an entry. ([65][gh-pull-0065])

Changed

- Update the minimum depending version of crossbeam-channel from v0.5.0 to v0.5.2.
([67][gh-pull-0067])