Fix mostly-theoretical data race when popping from SPSC queues#149
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nyanpasu64 merged 1 commit intomasterfrom Jun 23, 2022
Merged
Fix mostly-theoretical data race when popping from SPSC queues#149nyanpasu64 merged 1 commit intomasterfrom
nyanpasu64 merged 1 commit intomasterfrom
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The reader loses access to the front pointer as soon as it pops from the queue, since from that point onward, the writer can overwrite it with a new message. Instead the reader must finish using the pointer or copy the value out, before popping from the queue. This bug terrifies me.
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The reader loses access to the front pointer as soon as it pops from the queue, since from that point onward, the writer can overwrite it with a new message. Instead the reader must finish using the pointer or copy the value out, before popping from the queue.
This bug terrifies me, that I managed to write it, not catch it reviewing my own code despite years of atomic threading experience, and only realized I made a mistake weeks later, when reading an paper (https://lmax-exchange.github.io/disruptor/files/Disruptor-1.0.pdf).