What is fmcd?
It's the Fedimint Client Daemon — software for participating in a Fedimint (https://fedimint.org/) federation, which is a privacy-preserving Bitcoin custody protocol using
threshold multisig. It was installed as an Archipelago service and started on June 24, immediately joining federation 2debd071....
---
Why it's burning ~94% CPU:
The logs reveal a compounding networking problem:
1. Multiple Iroh P2P endpoints spawned in parallel — at startup, fmcd spun up at least 6 separate Iroh (QUIC-based P2P) endpoints (ab09514c69, 93a1e68c6a, 97ee1e4037,
1ed3b3083f, fe30639e2a, 1341f22c78), each with its own DHT instance and relay connections. This is likely more than intended.
2. Relay failures causing spin — https://use1-1.relay.n0.iroh-canary.iroh.link./ repeatedly fails to connect, and all those endpoints are constantly retrying. There were also
"failed to send ping: queues full" warnings, meaning network queues are overflowing.
3. DHT bootstrap stuck — since Jun 25, the only log entries are "Could not bootstrap the routing table" every 15–30 minutes. The Mainline DHT can't find peers, so the Iroh
discovery layer keeps spinning trying to locate federation guardians.
4. pkarr identity conflict — "A different SignedPacket is being concurrently published for the same PublicKey" — multiple Iroh endpoints are competing to publish the same
identity to the DHT, another sign of the parallel-endpoint problem.
Notably: the RocksDB database has only done 60 writes in 4 days — the actual Fedimint wallet logic is barely active. All the CPU is pure networking churn.
---
What to do:
This looks like a bug or misconfiguration in how Archipelago's Fedimint service is configured — likely related to Iroh spawning too many endpoints or a network path issue
(NAT/firewall blocking DHT). Restarting the container may help temporarily:
podman restart fedimint-clientd
But the root cause is likely worth reporting to the Archipelago project.
Screenshots
No response
### Description
archy-x250-pa was running hot so I checked it.
### Steps to Reproduce
Start fedimin?
### Expected Behavior
App should start and run smoothly
### Actual Behavior
Consuming lots of CPU and Disk I think
### Archipelago Version
1.7.99-alpha
### Hardware
x86_64 (Intel/AMD)
### Relevant Logs
```shell
What is fmcd?
It's the Fedimint Client Daemon — software for participating in a Fedimint (https://fedimint.org/) federation, which is a privacy-preserving Bitcoin custody protocol using
threshold multisig. It was installed as an Archipelago service and started on June 24, immediately joining federation 2debd071....
---
Why it's burning ~94% CPU:
The logs reveal a compounding networking problem:
1. Multiple Iroh P2P endpoints spawned in parallel — at startup, fmcd spun up at least 6 separate Iroh (QUIC-based P2P) endpoints (ab09514c69, 93a1e68c6a, 97ee1e4037,
1ed3b3083f, fe30639e2a, 1341f22c78), each with its own DHT instance and relay connections. This is likely more than intended.
2. Relay failures causing spin — https://use1-1.relay.n0.iroh-canary.iroh.link./ repeatedly fails to connect, and all those endpoints are constantly retrying. There were also
"failed to send ping: queues full" warnings, meaning network queues are overflowing.
3. DHT bootstrap stuck — since Jun 25, the only log entries are "Could not bootstrap the routing table" every 15–30 minutes. The Mainline DHT can't find peers, so the Iroh
discovery layer keeps spinning trying to locate federation guardians.
4. pkarr identity conflict — "A different SignedPacket is being concurrently published for the same PublicKey" — multiple Iroh endpoints are competing to publish the same
identity to the DHT, another sign of the parallel-endpoint problem.
Notably: the RocksDB database has only done 60 writes in 4 days — the actual Fedimint wallet logic is barely active. All the CPU is pure networking churn.
---
What to do:
This looks like a bug or misconfiguration in how Archipelago's Fedimint service is configured — likely related to Iroh spawning too many endpoints or a network path issue
(NAT/firewall blocking DHT). Restarting the container may help temporarily:
podman restart fedimint-clientd
But the root cause is likely worth reporting to the Archipelago project.
```
### Screenshots
_No response_
Mitigated: fmcd (fedimint-clientd) is CPU-capped at 1 core in its manifest — disk and the signed catalog both — with a comment documenting the iroh relay/hole-punch hot-loop, and the fmcd-run watchdog restarts a sustained-hot instance. A stuck fmcd can no longer starve the node. Reopen if it still runs hot within the cap.
Mitigated: fmcd (fedimint-clientd) is CPU-capped at 1 core in its manifest — disk and the signed catalog both — with a comment documenting the iroh relay/hole-punch hot-loop, and the fmcd-run watchdog restarts a sustained-hot instance. A stuck fmcd can no longer starve the node. Reopen if it still runs hot within the cap.
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Description
archy-x250-pa was running hot so I checked it.
Steps to Reproduce
Start fedimin?
Expected Behavior
App should start and run smoothly
Actual Behavior
Consuming lots of CPU and Disk I think
Archipelago Version
1.7.99-alpha
Hardware
x86_64 (Intel/AMD)
Relevant Logs
Screenshots
No response
Mitigated: fmcd (fedimint-clientd) is CPU-capped at 1 core in its manifest — disk and the signed catalog both — with a comment documenting the iroh relay/hole-punch hot-loop, and the fmcd-run watchdog restarts a sustained-hot instance. A stuck fmcd can no longer starve the node. Reopen if it still runs hot within the cap.