cosim: Remove unnecessary allocations and copying in cosim-plugin#816
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Giftzwerg02 merged 4 commits intomasterfrom Mar 24, 2026
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cosim: Remove unnecessary allocations and copying in cosim-plugin#816Giftzwerg02 merged 4 commits intomasterfrom
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Nice! This reminds me of the ringbuffer synchronization in the OS lecture ^^
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My intuition was that letting a QEMU-client collect all the data and then just copy into the ringbuffer when done (asking for a mutex-lock only for copying) would be better than getting the mutex lock first and writing directly into the ringbuffer.
That was just wrong, a) because copying seems to take a considerable amount of time and b) because the mutex is only required when checking/waiting if the buffer is writable.
Removing this indirection using a simple refactor gains roughly 2-3x performance for the cosim!