[FIXED] Deadlock when accessing subscriptions map on consumer #1671
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This fixes an issue where a deadlock could occur when calling `Stop()` or `Drain()` on `ConsumeContext` or `MessagesContext` and then calling `Consume` or `Messages` immediately. Switched to using a type-safe implementation of `sync.Map` for subscriptions map instead of locking the whole consumer state. Additionally, changed the type of atomic flags from `uint32` to `atomic.UInt32` to avoid acciental non-atomic reads/writes. Signed-off-by: Piotr Piotrowski <piotr@synadia.com>
Jarema
requested changes
Jul 11, 2024
internal/syncx/map.go
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| return previous.(V), loaded | ||
| } | ||
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| func (m *Map[K, V]) Len() int { |
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I believe this is not concurrent safe.
Maybe add additional field, like
count atomic.Int64and increment/decrement it every time we change the map?
That would also make Len() more performant, I think for a very low price elsewhere?
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Having a counter would not work since e.g. when using Store() we don't know whether the value is added to the map or updated. I agree that it may be racy, I'll think of another solution to not have to use Len() at all.
Signed-off-by: Piotr Piotrowski <piotr@synadia.com>
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piotrpio
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This fixes an issue where a deadlock could occur when calling `Stop()` or `Drain()` on `ConsumeContext` or `MessagesContext` and then calling `Consume` or `Messages` immediately. Switched to using a type-safe implementation of `sync.Map` for subscriptions map instead of locking the whole consumer state. Additionally, changed the type of atomic flags from `uint32` to `atomic.UInt32` to avoid accidental non-atomic reads/writes. Signed-off-by: Piotr Piotrowski <piotr@synadia.com> --------- Signed-off-by: Piotr Piotrowski <piotr@synadia.com>
piotrpio
added a commit
that referenced
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Aug 15, 2024
This fixes an issue where a deadlock could occur when calling `Stop()` or `Drain()` on `ConsumeContext` or `MessagesContext` and then calling `Consume` or `Messages` immediately. Switched to using a type-safe implementation of `sync.Map` for subscriptions map instead of locking the whole consumer state. Additionally, changed the type of atomic flags from `uint32` to `atomic.UInt32` to avoid accidental non-atomic reads/writes. Signed-off-by: Piotr Piotrowski <piotr@synadia.com> --------- Signed-off-by: Piotr Piotrowski <piotr@synadia.com>
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This fixes an issue where a deadlock could occur when calling
Stop()orDrain()onConsumeContextorMessagesContextand then callingConsumeorMessagesimmediately.Switched to using a type-safe implementation of
sync.Mapfor subscriptions mapinstead of locking the whole consumer state.
Additionally, changed the type of atomic flags from
uint32toatomic.UInt32to avoid acciental non-atomic reads/writes.
Signed-off-by: Piotr Piotrowski piotr@synadia.com