Bitcoin full node and query server
Nov 5, 2024
View in context in the libbitcoin Slack #general mirror.
josie18:43
somewhat unrelated, im very curious what insights you guys have regarding mmap'd db architectures. ive been exploring mdbx as a replacement for leveldb in core as sort of a moonshot side experiment, and mdbx (fork of lmdb) is essentially a mmap'd shadow paged btree. we saw some really promising benchmarks, but also a ton of write amplification. curious if you guys have any insights, since it seems you've rolled your own mmaped db architecture?
evoskuil19:36
We tossed out the previous iteration and started over due to these issues. It cost a couple years at least. But the learning helped us understand how to achieve fault tolerance and reliability (with much stronger guarantees than BC), as well as achieving hot file system backup - which were all original goals of Amir's when he started with mmap. Finally, we have learned how to manage thrashing, but it's a minefield sometimes.
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