9 lines
1.2 KiB
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9 lines
1.2 KiB
Plaintext
== Why is this an issue?
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A shared resource refers to a resource or data that can be accessed or modified by multiple https://en.wikipedia.org/wiki/Thread_(computing)[threads] or concurrent parts of a program. It could be any piece of data, object, file, database connection, or system resource that needs to be accessed or manipulated by multiple parts of a program concurrently.
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Shared resources should not be used for https://en.wikipedia.org/wiki/Lock_(computer_science)[locking] as it increases the chance of https://en.wikipedia.org/wiki/Deadlock[deadlocks]. Any other thread could acquire (or attempt to acquire) the same lock while doing some operation, without knowing that the resource is meant to be used for locking purposes.
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One case of this is strings, which are https://en.wikipedia.org/wiki/Interning_(computer_science)[interned] by the runtime. This means that each string instance is immutable and stored, and then is reused everywhere it is referenced.
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Instead, a dedicated private `object` instance should be used for each shared resource. Making the lock-specific object `private` guarantees that the access to it is as minimal as possible, in order to avoid deadlocks or lock contention. |