fix race condition#3344
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antiochp merged 1 commit intoJun 10, 2020
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quentinlesceller
approved these changes
Jun 9, 2020
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We were actually updating the
header_headtoo early, after applying headers to the sync MMR, but before we actually apply the headers to the header MMR.The process is roughly -
update header_head(leads to race condition)This PR fixes the issue by simply skipping the redundant (and incorrect) interim update.
We don't normally see this during a fast sync on mainnet or floonet as we are very likely to receive a new latest header during the sync process.
I noticed this a couple of times on usertesting while testing fast sync with NRD kernels and here the fast sync is fast and we are more likely to hit the race condition.