Crates / Compare / parking_lot vs async-lock
Rust crates side by side · data Oct 24, 2026
parking_lot vs async-lock
Short answerBy steady daily use, parking_lot is bigger: 2,961,161 real downloads a day against 818,501 for async-lock (3.6x). 8,755 crates depend on parking_lot and 374 on async-lock. parking_lot last shipped 3 days ago, async-lock 10 months ago.
parking_lot
Widely usedWidely used and steady.
8,755 crates depend on it; downloads jump on release days (1.4x the baseline).
More compact and efficient implementations of the standard synchronization primitives.
async-lock
EstablishedEstablished and steady.
374 crates depend on it; no release in the last 90 days, so its count is all steady use.
Async synchronization primitives
parking_lotasync-lock · 100% = that crate's normal quiet day, so a spike to 300% is triple its usual traffic
How they relate
- Often used together: 1 tracked crate depend on both (moka). They are not always either/or.
Every number, side by side
| Same window, same method | parking_lot | async-lock |
|---|---|---|
| Real downloads a day | 2,961,161 | 818,501 |
| Crates that depend on it | 8,755 | 374 |
| Last release | 0.13.0, 3 days ago | 3.4.2, 10 months ago |
| Trend vs the field | -8% | +4% |
| Release-window share | 3.4% | 0.0% |
| Downloads in the window | 252,874,388 | 74,610,605 |
| All-time downloads | 1,195,165,591 | 328,182,464 |
| Versions published | 59 | 32 |
| License | MIT OR Apache-2.0 | Apache-2.0 OR MIT |
| MSRV | 1.95 | 1.85 |
| First published | May 13, 2016 | May 22, 2019 |
Which to pick
- Downloads tell you what is common, not what fits. Each crate's own description above says what it is for; when the jobs differ, pick by the job.
- When both fit, prefer the one more crates depend on (parking_lot, 8,755 dependents): more eyes, more answered questions, and you may already have it in your tree.
- Check the release dates against your own pace: parking_lot 3 days ago, async-lock 10 months ago.
Also in this space
Method
Real downloads = the median day with no release that day or the day before, from the crates.io API (Jul 27, 2026 to Oct 23, 2026). Raw crates.io counts include CI and bots and run high (why); the method is from our 90-day study.
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