Fix lock ordering deadlock in StateManager#55
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set_desired_chunks acquired state before datasets_index, while run() acquires them in the opposite order — a classic AB-BA pattern that could deadlock when a new assignment arrives concurrently with the download loop. Align the order with run() (datasets_index then state). Introduced in subsquid#38 when set_desired_chunks and set_datasets_index were merged into one function without aligning lock acquisition order.
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Great catch! It may explain why we observed hanging subroutines occasionally. Thank you for the contribution! I would suggest to also change the order of these fields in the |
kalabukdima
approved these changes
May 12, 2026
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@kalabukdima done, please take a look |
kalabukdima
approved these changes
May 18, 2026
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set_desired_chunks acquired state before datasets_index, while run() acquires them in the opposite order — a classic AB-BA pattern that could deadlock when a new assignment arrives concurrently with the download loop. Align the order with run() (datasets_index then state).
Introduced in #38 when set_desired_chunks and set_datasets_index were merged into one function without aligning lock acquisition order.