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I'm using bitcoin core version 0.12.1 (To say precisely, I'm using addrindex patched bitcoin core by btcdrak)

I expected that mempool was maintained after restart bitcoind but that was deleted.

As far as I know that mempool is stored in chainstate/* directory as LevelDB data. I read this article. What is the database for?

Can you describe this is why and how can I avoid it. Sometimes, I have to restart my bitcoind for some reasons (like system maintanance). In that time I want to maintain the mempool data. Getting mempool data from peers..? takes a long time.

getmempoolinfo before bitcoind restart

$ curl --user 'xxx:yyy' --data-binary '{"jsonrpc":"1.0","id":"curltext","method":"getmempoolinfo","params":[]}' -H 'content-type:text/plain;' http://127.0.0.1:8332
{"result":{"size":15350,"bytes":120107104,"usage":258574880,"maxmempool":300000000,"mempoolminfee":0.00000000},"error":null,"id":"curltext"}

getmempoolinfo after bitcoind restart

$ curl --user 'xxx:yyy' --data-binary '{"jsonrpc":"1.0","id":"curltext","method":"getmempoolinfo","params":[]}' -H 'content-type:text/plain;' http://127.0.0.1:8332
{"result":{"size":0,"bytes":0,"usage":0,"maxmempool":300000000,"mempoolminfee":0.00000000},"error":null,"id":"curltext"}
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zono
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1 Answers1

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So far, no released versions of Bitcoin Core exist that store the mempool on disk. That's why it's called the mempool; it's a pool of unconfirmed transactions kept in memory.

Version 0.14 is expected to introduce automatic dumping of the mempool to disk at shutdown.

Pieter Wuille
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  • "Version 0.14 is expected to introduce automatic dumping of the mempool to disk at shutdown." This was indeed done: https://github.com/bitcoin/bitcoin/blob/master/doc/release-notes/release-notes-0.14.0.md#retaining-the-mempool-across-restarts – Larry Ruane Nov 07 '22 at 04:14