Howard Chu @ Symas on Nostr: A post from #ArcticDB about using #LMDB on tmpfs for ephemeral DBs where persistence ...
A post from #ArcticDB about using #LMDB on tmpfs for ephemeral DBs where persistence doesn't matter, just performance.
https://docs.arcticdb.io/tutorials/lmdb_and_in_memory/This is stupid. Just use LMDB on a regular filesystem, and run it with MDB_NOSYNC. In that case most I/Os will only get as far as the filesystem cache anyway, so it will be the same perf as tmpfs.
Using tmpfs for LMDB is dumb because RAM allocated there is stuck. While RAM in fscache can still be repurposed if needed.
Published at
2023-10-23 04:40:37Event JSON
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"content": "A post from #ArcticDB about using #LMDB on tmpfs for ephemeral DBs where persistence doesn't matter, just performance. https://docs.arcticdb.io/tutorials/lmdb_and_in_memory/\n\nThis is stupid. Just use LMDB on a regular filesystem, and run it with MDB_NOSYNC. In that case most I/Os will only get as far as the filesystem cache anyway, so it will be the same perf as tmpfs.\n\nUsing tmpfs for LMDB is dumb because RAM allocated there is stuck. While RAM in fscache can still be repurposed if needed.",
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