asyncio.Semaphore
A coroutine-level synchronization primitive in the Python asyncio library that controls concurrent access to a limited resource through a counter. When the count reaches zero, waiting coroutines are suspended without blocking operating system threads. It is used to implement concurrency control patterns such as connection pools and rate limiting.
Timeline (last 90 days)
asyncio.Semaphore is a coroutine-level synchronization primitive whose counter is managed single-threadedly by the event loop; acquire() suspends the coroutine rather than blocking the thread when the count is zero.
asyncio.Semaphore's release() does not verify whether the caller holds a permit, so neither erroneous calls nor missed calls raise an error immediately, making leaks stealthy.
All Facts (2)
asyncio.Semaphore is a coroutine-level synchronization primitive whose counter is managed single-threadedly by the event loop; acquire() suspends the coroutine rather than blocking the thread when the count is zero.
50%Unverifiedasyncio.Semaphore's release() does not verify whether the caller holds a permit, so neither erroneous calls nor missed calls raise an error immediately, making leaks stealthy.
50%