Keep capacity when dropping pending reads in the stream channel #447
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Motivation: When the stream channel has closed it drops all of its pending reads. It does this by calling 'removeAll()' on its CircularBuffer. The buffers underlying storage is emptied and then a `nil` is appended (internally CircularBuffer is never empty) which triggers an allocation. Modifications: - Remove all but keep capacity Result: Fewer allocations
gjcairo
reviewed
Jul 5, 2024
| @@ -728,7 +728,7 @@ private extension HTTP2StreamChannel { | |||
| /// Drop all pending reads. | |||
| private func dropPendingReads() { | |||
| /// We don't need to report the dropped reads, just remove them all. | |||
| self.pendingReads.removeAll() | |||
| self.pendingReads.removeAll(keepingCapacity: true) | |||
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Should we worry about this potentially keeping an unneeded/too-big capacity for the duration of the stream?
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No, this is only called when the channel is closing.
gjcairo
approved these changes
Jul 8, 2024
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Motivation:
When the stream channel has closed it drops all of its pending reads. It does this by calling 'removeAll()' on its CircularBuffer. The buffers underlying storage is emptied and then a
nilis appended (internally CircularBuffer is never empty) which triggers an allocation.Modifications:
Result:
Fewer allocations