chore: release v1.7.47-alpha

Sync-perf tuning for bitcoin/bitcoin-core/bitcoin-knots/electrumx.

- Drop the --cpus=2 cap on bitcoin/electrumx variants. Script verification
  is parallelizable; the cap halved IBD speed on 4-8 core machines.
- Bump bitcoin --memory 4g→8g so dbcache=4096 has headroom for mempool +
  connection buffers + I/O. 4g was OOM-prone during heavy IBD.
- Bump electrumx --memory 1g→2g + add CACHE_MB=2048 + MAX_SEND=10MB.
- bitcoin-core CLI args gain -dbcache=4096 -par=0 -maxconnections=125.
- bitcoin-knots manifest matched (1024MB pruned / 4096MB full + par=0).

Future v2: host-RAM-aware dbcache scaling.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

core/archipelago/src/api/rpc/package/config.rs

@@ -244,13 +244,19 @@ pub(super) fn get_health_check_args(app_id: &str, _rpc_pass: &str) -> Vec<String
 /// Get per-app memory limit.
 pub(super) fn get_memory_limit(app_id: &str) -> &'static str {
     match app_id {
-        // Heavy apps
-        "bitcoin" | "bitcoin-core" | "bitcoin-knots" => "4g",
+        // Heavy apps. Bitcoin: dbcache uses ~4GB; the daemon also needs
+        // headroom for mempool + connection buffers + script-verifier
+        // memory + I/O. 4g caused OOM-cascades during IBD. 8g is the
+        // floor; ideally this would be host-RAM aware (next pass).
+        "bitcoin" | "bitcoin-core" | "bitcoin-knots" => "8g",
+        // ElectrumX: bumped from 1g to 2g so its CACHE_MB has somewhere
+        // to live during initial blockchain indexing. CACHE_MB=2048 in
+        // env vars below requires this much.
+        "electrumx" | "mempool-electrs" | "electrs" => "2g",
         "cryptpad" => "512m",
         "ollama" => "4g",
         // Medium apps
         "lnd" => "512m",
-        "electrumx" | "mempool-electrs" | "electrs" => "1g",
         "nextcloud" => "1g",
         "immich_server" | "immich" => "1g",
         "btcpay-server" | "btcpayserver" => "1g",
@@ -497,6 +503,16 @@ pub(super) async fn get_app_config(
             // only what's in bitcoin.conf + argv. The shared bitcoin.conf
             // carries rpcauth; we inject the networking flags as CLI args so
             // RPC is reachable from the bitcoin-ui companion container.
+            //
+            // Sync-speed flags:
+            //   -dbcache=4096 — UTXO set cache; 4GB is the sweet spot before
+            //     diminishing returns. Container has --memory=8g now so
+            //     there's headroom for mempool + connections.
+            //   -par=0       — use all available cores for script
+            //     verification (defaults to NCPU-1 capped at 16). Was
+            //     effectively pinned at 2 by --cpus=2 (now removed).
+            //   -maxconnections=125 — default but explicit, so ops can
+            //     tune downward on bandwidth-constrained nodes.
             Some(vec![
                 "-server=1".to_string(),
                 "-rpcbind=0.0.0.0".to_string(),
@@ -504,6 +520,9 @@ pub(super) async fn get_app_config(
                 "-rpcport=8332".to_string(),
                 "-printtoconsole=1".to_string(),
                 "-datadir=/home/bitcoin/.bitcoin".to_string(),
+                "-dbcache=4096".to_string(),
+                "-par=0".to_string(),
+                "-maxconnections=125".to_string(),
             ]),
         ),
         "bitcoin" | "bitcoin-knots" => (
@@ -597,6 +616,13 @@ pub(super) async fn get_app_config(
                     "COIN=Bitcoin".to_string(),
                     "DB_DIRECTORY=/data".to_string(),
                     "SERVICES=tcp://:50001,rpc://0.0.0.0:8000".to_string(),
+                    // Sync-speed: bigger LRU/write cache during initial
+                    // history index. Default is 1200MB, container now
+                    // gets 2g (config.rs::get_memory_limit) so 2048 fits.
+                    "CACHE_MB=2048".to_string(),
+                    // Block-fetcher concurrency — defaults are conservative
+                    // for shared hosts; 4 is plenty for one bitcoind backend.
+                    "MAX_SEND=10000000".to_string(),
                 ],
                 None,
                 None,

core/archipelago/src/api/rpc/package/install.rs

@@ -567,7 +567,18 @@ impl RpcHandler {
         let memory_limit = get_memory_limit(package_id);
         let mem_arg = format!("--memory={}", memory_limit);
         run_args.push(&mem_arg);
-        run_args.push("--cpus=2");
+        // Bitcoin (and friends) need every core they can get during initial
+        // blockchain download — script verification is parallelizable and
+        // the limiting factor on most home boxes. --cpus=2 was halving sync
+        // speed for 4-8 core machines. ElectrumX likewise scales with cores
+        // during its initial reorg/indexing phase.
+        let cpu_capped = !matches!(
+            package_id,
+            "bitcoin" | "bitcoin-core" | "bitcoin-knots" | "electrumx" | "electrs" | "mempool-electrs"
+        );
+        if cpu_capped {
+            run_args.push("--cpus=2");
+        }
 
         // Uptime Kuma image entrypoint (`extra/entrypoint.sh`) attempts
         // `setpriv --clear-groups` and fails under our rootless + cap-drop