Bitcoind JSON-RPC is very slow for dumping GetRawTransaction even with a high perf computer. #12224

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I'm running a JSON/RPC query program, in mode parallel with 100 Threads dumping GetRawTransaction . My bitcoin.conf is:

server=1 txindex=1 dbcache=2048 rpcworkqueue=128 rpcthreads=128 rpctimeout=220

This remains very slow the CPU usage is only 20% the disks 1% (very fast M2 SSDs). This is like there is a lock or a json/rpc serialization. Impossible to go faster.

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Windows 10 - 8700K with 32GB and M2 Samsung 960 SSD

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You could try to use REST (see https://github.com/bitcoin/bitcoin/blob/master/doc/REST-interface.md):

GET /rest/tx/<TX-HASH>.<bin|hex|json>

Given a transaction hash: returns a transaction in binary, hex-encoded binary, or JSON formats.

If you use the binary format, the serialization overhead will be smallest.

Edit: Also, are you re-using the HTTP connection, instead of closing and opening a new one every time? Doing that is also very important for performance.

Perfect!