Development Update — April 21

Skywire: DHT Full Node Discovery and Bulk Sync

PR #2321 adds the infrastructure for DHT nodes to find each other and synchronize their data stores:

GetItems RPC (method 5) — new DHT RPC for bulk data sync. Supports salt filtering (dmsg, tp, svc) and sequence threshold for incremental sync. Paginated with limit + hasMore indicator. 30-second timeout for bulk transfers.

Full node advertisement — full nodes publish their PK under salt “fullnode” every 5 minutes. FindFullNodes() returns bootstrap peers as known full nodes. This lets any visor discover which peers have the complete dataset.

skywire cli visor dht sync — sync from the default bootstrap peer or a specific full node. --salt flag filters by namespace. This is the manual trigger for bulk sync; automated sync happens periodically.

skywire cli tp all — list all transports from transport discovery, or from the local DHT store if available. Auto-detects whether the visor has DHT data and serves locally when possible, falling back to HTTP.

DMSG server self-publication — servers publish their entry (PK, address, max_sessions, dht_bootstrap) under salt “dmsg-server” every 5 minutes. Visors can discover DMSG servers from DHT without DMSG discovery HTTP. This is the key enabler for bootstrapping without centralized discovery.

Skip TPD HTTP re-registration when DHT is active — once a visor has at least 1 DHT peer, SetDHTHandlesRegistration(true) disables the 90-second HTTP re-registration loop with the transport discovery. Transport data is still published to DHT every 60 seconds. This reduces TPD HTTP load by approximately 80%.

DHT status in visor info — skywire cli visor info now shows DHT mode (full node / regular), peer count, and stored items.

Skywire: Visor RPC Over Transports

PR #2320 adds a completely new way to manage visors: RPC over Skywire transports.

VisorRPCPacket (type 14) on route ID 0 — a new transport-level frame type that carries RPC traffic directly over STCPR/SUDPH transports. No DMSG required. No routes required. Just the raw transport.

Whitelist-gated access — the remote PK is checked against the hypervisor PKs and dmsgpty whitelist. Only authorized operators can RPC into a visor over transports.

skywire cli visor tp-rpc <remote-pk> <method> — call a remote visor’s RPC method over the transport layer:

skywire cli visor tp-rpc <pk> Overview
skywire cli visor tp-rpc <pk> Health
skywire cli visor tp-rpc <pk> Summary

The local visor acts as proxy: opens a VStream to the remote visor, forwards the RPC call, returns the result. This gives operators an alternative management path when DMSG is unavailable.

Skywire: DHT Bootstrap Improvements

Periodic bootstrap with retry — bootstrap now retries every 30 seconds until at least one peer is found, then every 5 minutes for maintenance. Previously it ran once at startup and gave up permanently on failure.

Fix DHT transport for DMSG servers — DMSG servers have server-type discovery entries, not client entries, so DialStream rejected them. Now falls back to the existing yamux session (which the visor already has) when DialStream fails.

DHT bootstrap indicator — DMSG server entries in the discovery now include a DHTBootstrap field indicating whether they run DHT. Visors use this to select bootstrap peers.

Disable DHT in deployment services — all 6 deployment services now set DisableDHT: true. DMSG servers are the DHT nodes; services don’t need their own Kademlia instances. Reduces redundant nodes on the same machine.

Skywire: DHT Mirroring Architecture

RedisMirror (pkg/dht/mirror_redis.go) — writes DHT entries directly to Redis without a local DHT node. Used by deployment services with DisableDHT=true. DMSG servers read the same Redis and serve via Kademlia.

MutableItemTarget helper — extracted for standalone use: computes SHA256(pk || salt) for DHT key derivation without needing a full MutableItem.

Documentation — docs/DHT_ARCHITECTURE.md added covering node types (DMSG servers as full nodes, visors as regular, services as mirrors), persistence backends, deployment topologies, and data flow.

Skywire: Performance Optimizations

3709c1148 Fix dmsg-discovery 84% CPU — the DHT EntryMirror was doing a full Kademlia Put for every entry update, which involves iterative lookups and multiple network round-trips. Replaced with RedisMirror that writes directly to Redis. CPU dropped from 84% to normal.

ba6b9b7af Optimize noise keypair pool: 8x burst, skip debug validation — the noise handshake pre-generates keypairs in a pool. Pool refill burst increased from 1 to 8. Debug-mode signature validation on pool fetch removed (it was verifying the keypair was valid every time it was used, which is redundant since it was valid when generated).

903b9798e Optimize TPD: batch Redis pipeline for transport registration — transport registrations now use Redis pipelines instead of individual commands. A single registration with 2 edges went from 6 sequential Redis round-trips to 1 pipelined batch.

502255b28 Optimize SD: combine UpdateService + RecordHeartbeat — two separate Redis pipelines merged into one, halving the per-registration Redis round-trips.