Merge #6311: fix: 2 follow-ups for PeriodicStats

802efc5 fix: update DEFAULT_STATSD_HOST (UdjinM6)
44d7806 fix: use correct rpc interruption point in `PeriodicStats` (UdjinM6)

Pull request description:

  ## Issue being fixed or feature implemented
  - 5c2c2b3: dash-qt with stats enabled crashes
  - b92ce3d: help text for `-statshost` is misleading

  ## What was done?

  ## How Has This Been Tested?

  ## Breaking Changes

  ## Checklist:
  - [ ] I have performed a self-review of my own code
  - [ ] I have commented my code, particularly in hard-to-understand areas
  - [ ] I have added or updated relevant unit/integration/functional/e2e tests
  - [ ] I have made corresponding changes to the documentation
  - [ ] I have assigned this pull request to a milestone _(for repository code-owners and collaborators only)_

ACKs for top commit:
  knst:
    utACK 802efc5

Tree-SHA512: 093229a96e726dc30c8aef210046bebaef040179785fd8be20de5052d766b361426f18f41338ef059997e820645faa7fba424f056be2f6454ca3190f8c3c0906

src/init.cpp

@@ -837,12 +837,15 @@ static void StartupNotify(const ArgsManager& args)
 }
 #endif
 
-static void PeriodicStats(ArgsManager& args, ChainstateManager& chainman, const CTxMemPool& mempool)
+static void PeriodicStats(NodeContext& node)
 {
     assert(::g_stats_client->active());
+    const ArgsManager& args = *Assert(node.args);
+    ChainstateManager& chainman = *Assert(node.chainman);
+    const CTxMemPool& mempool = *Assert(node.mempool);
     CCoinsStats stats{CoinStatsHashType::NONE};
     chainman.ActiveChainstate().ForceFlushStateToDisk();
-    if (WITH_LOCK(cs_main, return GetUTXOStats(&chainman.ActiveChainstate().CoinsDB(), std::ref(chainman.m_blockman), stats, RpcInterruptionPoint, chainman.ActiveChain().Tip()))) {
+    if (WITH_LOCK(cs_main, return GetUTXOStats(&chainman.ActiveChainstate().CoinsDB(), chainman.m_blockman, stats, node.rpc_interruption_point, chainman.ActiveChain().Tip()))) {
         ::g_stats_client->gauge("utxoset.tx", stats.nTransactions, 1.0f);
         ::g_stats_client->gauge("utxoset.txOutputs", stats.nTransactionOutputs, 1.0f);
         ::g_stats_client->gauge("utxoset.dbSizeBytes", stats.nDiskSize, 1.0f);
@@ -2299,7 +2302,7 @@ bool AppInitMain(NodeContext& node, interfaces::BlockAndHeaderTipInfo* tip_info)
 
     if (::g_stats_client->active()) {
         int nStatsPeriod = std::min(std::max((int)args.GetArg("-statsperiod", DEFAULT_STATSD_PERIOD), MIN_STATSD_PERIOD), MAX_STATSD_PERIOD);
-        node.scheduler->scheduleEvery(std::bind(&PeriodicStats, std::ref(*node.args), std::ref(chainman), std::cref(*node.mempool)), std::chrono::seconds{nStatsPeriod});
+        node.scheduler->scheduleEvery(std::bind(&PeriodicStats, std::ref(node)), std::chrono::seconds{nStatsPeriod});
     }
 
     // ********************************************************* Step 11: import blocks

src/stats/client.cpp

@@ -34,12 +34,12 @@ std::unique_ptr<StatsdClient> g_stats_client;
 std::unique_ptr<StatsdClient> InitStatsClient(const ArgsManager& args)
 {
     auto is_enabled = args.GetBoolArg("-statsenabled", /*fDefault=*/false);
-    auto host = args.GetArg("-statshost", /*fDefault=*/"");
+    auto host = args.GetArg("-statshost", /*fDefault=*/DEFAULT_STATSD_HOST);
 
     if (is_enabled && host.empty()) {
         // Stats are enabled but host has not been specified, then use
-        // default host. This is to preserve old behavior.
-        host = DEFAULT_STATSD_HOST;
+        // default legacy host. This is to preserve old behavior.
+        host = "127.0.0.1";
     } else if (!host.empty()) {
         // Host is specified but stats are not explcitly enabled. Assume
         // that if a host has been specified, we want stats enabled. This

src/stats/client.h

@@ -19,7 +19,7 @@ class RawSender;
 /** Default port used to connect to a Statsd server */
 static constexpr uint16_t DEFAULT_STATSD_PORT{8125};
 /** Default host assumed to be running a Statsd server */
-static const std::string DEFAULT_STATSD_HOST{"127.0.0.1"};
+static const std::string DEFAULT_STATSD_HOST{""};
 /** Default prefix prepended to Statsd message keys */
 static const std::string DEFAULT_STATSD_PREFIX{""};
 /** Default suffix appended to Statsd message keys */