1 unstable release
Uses old Rust 2015
0.5.0 | Nov 12, 2018 |
---|
#47 in #rwlock
33KB
689 lines
Wide (Partitioned) Read Write Lock
This crate implements an enterprise-grade read-write lock, typically used for large data structures.
The lock is internally 8x partitioned, which allows it to scale much better with a large number of readers,
as compared to std::sync::RwLock
.
Even though this is a large lock, it has better performance characteristic for uncontended single reader
or single writer lock than std::sync::RwLock
.
The lock uses a contiguous 576 byte heap area to store its state, so it's not a light-weight lock. If you have a complex data structure that holds a GB of data, this would be an appropriate lock.
An interesting feature of this lock, beside its performance, is its Read->Write upgrade mechanics. The ReadGuard
allows an
upgrade to a write-lock and informs the user whether the upgrade succeeded atomically or not. This enables
the following pattern:
-
Read to see if the data structure is in a particular state (e.g. contains a value).
- if not, upgrade to a write lock
- if upgrade was not atomic, perform the (potentially expensive) read again
- write to the structure if needed
Usage
Add this to your Cargo.toml
:
[dependencies]
widerwlock = "0.5"
and this to your crate root:
extern crate widerwlock;
Rust Version Support
The minimum supported Rust version is 1.28 due to use of allocator api.
Dependencies
~0.6–0.9MB
~13K SLoC