perf: Shorten consensus cadence for low-latency perf clusters

Co-authored-by: Bart <11445373+bthomee@users.noreply.github.com>

.github/workflows/check-pr-description.yml

@@ -5,8 +5,17 @@ on:
     types:
       - checks_requested
   pull_request:
-    types: [opened, edited, reopened, synchronize, ready_for_review]
-    branches: [develop]
+    types:
+      - opened
+      - edited
+      - reopened
+      - synchronize
+      - ready_for_review
+    branches:
+      - develop
+      - "release-*"
+      - "release/*"
+      - "staging/*"
 
 jobs:
   check_description:

.github/workflows/check-pr-title.yml

@@ -5,8 +5,17 @@ on:
     types:
       - checks_requested
   pull_request:
-    types: [opened, edited, reopened, synchronize, ready_for_review]
-    branches: [develop]
+    types:
+      - opened
+      - edited
+      - reopened
+      - synchronize
+      - ready_for_review
+    branches:
+      - develop
+      - "release-*"
+      - "release/*"
+      - "staging/*"
 
 jobs:
   check_title:

cfg/xrpld-example.cfg

@@ -953,6 +953,21 @@
 #
 #   Optional keys for NuDB and RocksDB:
 #
+#       cache_size          Size of cache for database records. Default is 16384.
+#                           Setting this value to 0 will use the default value.
+#
+#       cache_age           Length of time in minutes to keep database records
+#                           cached. Default is 5 minutes. Setting this value to
+#                           0 will use the default value.
+#
+#                           Note: if cache_size or cache_age is not specified,
+#                           default values will be used for the unspecified
+#                           parameter.
+#
+#                           Note: the cache will not be created if online_delete
+#                           is specified, because the rotating NodeStore does
+#                           not use this cache).
+#
 #       fast_load           Boolean. If set, load the last persisted ledger
 #                           from disk upon process start before syncing to
 #                           the network. This is likely to improve performance

include/xrpl/beast/rfc2616.h

@@ -10,7 +10,6 @@
 #include <cctype>
 #include <iterator>
 #include <string>
-#include <string_view>
 #include <vector>
 
 namespace beast::rfc2616 {
@@ -182,7 +181,7 @@ splitCommas(FwdIt first, FwdIt last)
 
 template <class Result = std::vector<std::string>>
 Result
-splitCommas(std::string_view const& s)
+splitCommas(boost::beast::string_view const& s)
 {
     return splitCommas(s.begin(), s.end());
 }

include/xrpl/json/Output.h

@@ -1,19 +1,20 @@
 #pragma once
 
+#include <boost/beast/core/string.hpp>
+
 #include <functional>
 #include <string>
-#include <string_view>
 
 namespace json {
 
 class Value;
 
-using Output = std::function<void(std::string_view)>;
+using Output = std::function<void(boost::beast::string_view const&)>;
 
 inline Output
 stringOutput(std::string& s)
 {
-    return [&](std::string_view b) { s.append(b.data(), b.size()); };
+    return [&](boost::beast::string_view const& b) { s.append(b.data(), b.size()); };
 }
 
 /** Writes a minimal representation of a Json value to an Output in O(n) time.

include/xrpl/nodestore/Database.h

@@ -131,6 +131,10 @@ public:
         std::uint32_t ledgerSeq,
         std::function<void(std::shared_ptr<NodeObject> const&)>&& callback);
 
+    /** Remove expired entries from the positive and negative caches. */
+    virtual void
+    sweep() = 0;
+
     /** Gather statistics pertaining to read and write activities.
      *
      * @param obj Json object reference into which to place counters.

include/xrpl/nodestore/detail/DatabaseNodeImp.h

@@ -22,6 +22,32 @@ public:
         beast::Journal j)
         : Database(scheduler, readThreads, config, j), backend_(std::move(backend))
     {
+        std::optional<int> cacheSize, cacheAge;
+
+        if (config.exists("cache_size"))
+        {
+            cacheSize = get<int>(config, "cache_size");
+            if (cacheSize.value() < 0)
+                Throw<std::runtime_error>("Specified negative value for cache_size");
+        }
+
+        if (config.exists("cache_age"))
+        {
+            cacheAge = get<int>(config, "cache_age");
+            if (cacheAge.value() < 0)
+                Throw<std::runtime_error>("Specified negative value for cache_age");
+        }
+
+        if (cacheSize.has_value() || cacheAge.has_value())
+        {
+            cache_ = std::make_shared<TaggedCache<uint256, NodeObject>>(
+                "DatabaseNodeImp",
+                cacheSize.value_or(0),
+                std::chrono::minutes(cacheAge.value_or(0)),
+                stopwatch(),
+                j);
+        }
+
         XRPL_ASSERT(
             backend_,
             "xrpl::NodeStore::DatabaseNodeImp::DatabaseNodeImp : non-null "
@@ -73,7 +99,13 @@ public:
         std::uint32_t ledgerSeq,
         std::function<void(std::shared_ptr<NodeObject> const&)>&& callback) override;
 
+    void
+    sweep() override;
+
 private:
+    // Cache for database objects. This cache is not always initialized. Check
+    // for null before using.
+    std::shared_ptr<TaggedCache<uint256, NodeObject>> cache_;
     // Persistent key/value storage
     std::shared_ptr<Backend> backend_;
 

include/xrpl/nodestore/detail/DatabaseRotatingImp.h

@@ -55,6 +55,9 @@ public:
     void
     sync() override;
 
+    void
+    sweep() override;
+
 private:
     std::shared_ptr<Backend> writableBackend_;
     std::shared_ptr<Backend> archiveBackend_;

include/xrpl/server/detail/BaseWSPeer.h

@@ -18,7 +18,6 @@
 #include <algorithm>
 #include <functional>
 #include <list>
-#include <string_view>
 
 namespace xrpl {
 
@@ -50,7 +49,7 @@ private:
     bool pingActive_ = false;
     boost::beast::websocket::ping_data payload_;
     error_code ec_;
-    std::function<void(boost::beast::websocket::frame_type, std::string_view)>
+    std::function<void(boost::beast::websocket::frame_type, boost::beast::string_view)>
         controlCallback_;
 
 public:
@@ -139,7 +138,7 @@ protected:
     onPing(error_code const& ec);
 
     void
-    onPingPong(boost::beast::websocket::frame_type kind, std::string_view payload);
+    onPingPong(boost::beast::websocket::frame_type kind, boost::beast::string_view payload);
 
     void
     onTimer(error_code ec);
@@ -420,11 +419,11 @@ template <class Handler, class Impl>
 void
 BaseWSPeer<Handler, Impl>::onPingPong(
     boost::beast::websocket::frame_type kind,
-    std::string_view payload)
+    boost::beast::string_view payload)
 {
     if (kind == boost::beast::websocket::frame_type::pong)
     {
-        std::string_view const p(payload_.begin(), payload_.size());
+        boost::beast::string_view const p(payload_.begin());
         if (payload == p)
         {
             closeOnTimer_ = false;

src/libxrpl/json/Writer.cpp

@@ -9,7 +9,6 @@
 #include <set>  // IWYU pragma: keep
 #include <stack>
 #include <string>
-#include <string_view>
 #include <utility>
 #include <vector>
 
@@ -88,14 +87,14 @@ public:
     }
 
     void
-    output(std::string_view bytes)
+    output(boost::beast::string_view const& bytes)
     {
         markStarted();
         output_(bytes);
     }
 
     void
-    stringOutput(std::string_view bytes)
+    stringOutput(boost::beast::string_view const& bytes)
     {
         markStarted();
         std::size_t position = 0, writtenUntil = 0;

src/libxrpl/ledger/helpers/PermissionedDEXHelpers.cpp

@@ -3,6 +3,8 @@
 #include <xrpl/basics/Log.h>
 #include <xrpl/basics/base_uint.h>
 #include <xrpl/beast/utility/Journal.h>
+#include <xrpl/beast/utility/Zero.h>
+#include <xrpl/beast/utility/instrumentation.h>
 #include <xrpl/ledger/ReadView.h>
 #include <xrpl/ledger/helpers/CredentialHelpers.h>
 #include <xrpl/protocol/AccountID.h>
@@ -19,6 +21,16 @@ namespace xrpl::permissioned_dex {
 bool
 accountInDomain(ReadView const& view, AccountID const& account, Domain const& domainID)
 {
+    // Avoid constructing a zero-key PermissionedDomain keylet.
+    // keylet::permissionedDomain(uint256) uses the DomainID as the ledger key.
+    if (view.rules().enabled(fixCleanup3_2_0) && domainID == beast::kZero)
+    {
+        // LCOV_EXCL_START
+        UNREACHABLE("xrpl::permissioned_dex::accountInDomain : domainID is zero");
+        return false;
+        // LCOV_EXCL_STOP
+    }
+
     auto const sleDomain = view.read(keylet::permissionedDomain(domainID));
     if (!sleDomain)
         return false;

src/libxrpl/nodestore/DatabaseNodeImp.cpp

@@ -24,6 +24,13 @@ DatabaseNodeImp::store(NodeObjectType type, Blob&& data, uint256 const& hash, st
 
     auto obj = NodeObject::createObject(type, std::move(data), hash);
     backend_->store(obj);
+    if (cache_)
+    {
+        // After the store, replace a negative cache entry if there is one
+        cache_->canonicalize(hash, obj, [](std::shared_ptr<NodeObject> const& n) {
+            return n->getType() == NodeObjectType::Dummy;
+        });
+    }
 }
 
 void
@@ -32,9 +39,25 @@ DatabaseNodeImp::asyncFetch(
     std::uint32_t ledgerSeq,
     std::function<void(std::shared_ptr<NodeObject> const&)>&& callback)
 {
+    if (cache_)
+    {
+        std::shared_ptr<NodeObject> const obj = cache_->fetch(hash);
+        if (obj)
+        {
+            callback(obj->getType() == NodeObjectType::Dummy ? nullptr : obj);
+            return;
+        }
+    }
     Database::asyncFetch(hash, ledgerSeq, std::move(callback));
 }
 
+void
+DatabaseNodeImp::sweep()
+{
+    if (cache_)
+        cache_->sweep();
+}
+
 std::shared_ptr<NodeObject>
 DatabaseNodeImp::fetchNodeObject(
     uint256 const& hash,
@@ -42,32 +65,58 @@ DatabaseNodeImp::fetchNodeObject(
     FetchReport& fetchReport,
     bool duplicate)
 {
-    std::shared_ptr<NodeObject> nodeObject = nullptr;
-    Status status = Status::Ok;
+    std::shared_ptr<NodeObject> nodeObject = cache_ ? cache_->fetch(hash) : nullptr;
+    if (!nodeObject)
+    {
+        JLOG(j_.trace()) << "fetchNodeObject " << hash << ": record not "
+                         << (cache_ ? "cached" : "found");
 
-    try
-    {
-        status = backend_->fetch(hash, &nodeObject);
-    }
-    catch (std::exception const& e)
-    {
-        JLOG(j_.fatal()) << "fetchNodeObject " << hash
-                         << ": Exception fetching from backend: " << e.what();
-        rethrow();
-    }
+        Status status = Status::Ok;
+        try
+        {
+            status = backend_->fetch(hash, &nodeObject);
+        }
+        catch (std::exception const& e)
+        {
+            JLOG(j_.fatal()) << "fetchNodeObject " << hash
+                             << ": Exception fetching from backend: " << e.what();
+            rethrow();
+        }
 
-    switch (status)
+        switch (status)
+        {
+            case Status::Ok:
+                if (cache_)
+                {
+                    if (nodeObject)
+                    {
+                        cache_->canonicalizeReplaceClient(hash, nodeObject);
+                    }
+                    else
+                    {
+                        auto notFound = NodeObject::createObject(NodeObjectType::Dummy, {}, hash);
+                        cache_->canonicalizeReplaceClient(hash, notFound);
+                        if (notFound->getType() != NodeObjectType::Dummy)
+                            nodeObject = notFound;
+                    }
+                }
+                break;
+            case Status::NotFound:
+                break;
+            case Status::DataCorrupt:
+                JLOG(j_.fatal()) << "fetchNodeObject " << hash << ": nodestore data is corrupted";
+                break;
+            default:
+                JLOG(j_.warn()) << "fetchNodeObject " << hash << ": backend returns unknown result "
+                                << static_cast<int>(status);
+                break;
+        }
+    }
+    else
     {
-        case Status::Ok:
-        case Status::NotFound:
-            break;
-        case Status::DataCorrupt:
-            JLOG(j_.fatal()) << "fetchNodeObject " << hash << ": nodestore data is corrupted";
-            break;
-        default:
-            JLOG(j_.warn()) << "fetchNodeObject " << hash << ": backend returns unknown result "
-                            << static_cast<int>(status);
-            break;
+        JLOG(j_.trace()) << "fetchNodeObject " << hash << ": record found in cache";
+        if (nodeObject->getType() == NodeObjectType::Dummy)
+            nodeObject.reset();
     }
 
     if (nodeObject)

src/libxrpl/nodestore/DatabaseRotatingImp.cpp

@@ -113,6 +113,12 @@ DatabaseRotatingImp::store(NodeObjectType type, Blob&& data, uint256 const& hash
     storeStats(1, nObj->getData().size());
 }
 
+void
+DatabaseRotatingImp::sweep()
+{
+    // Nothing to do.
+}
+
 std::shared_ptr<NodeObject>
 DatabaseRotatingImp::fetchNodeObject(
     uint256 const& hash,

src/libxrpl/tx/transactors/dex/OfferCreate.cpp

@@ -94,6 +94,12 @@ OfferCreate::preflight(PreflightContext const& ctx)
     if (tx.isFlag(tfHybrid) && !tx.isFieldPresent(sfDomainID))
         return temINVALID_FLAG;
 
+    // A zero DomainID is invalid for a PermissionedDomain ledger entry because
+    // keylet::permissionedDomain(uint256) uses the DomainID as the ledger key.
+    if (auto const domainID = tx[~sfDomainID];
+        ctx.rules.enabled(fixCleanup3_2_0) && domainID && *domainID == beast::kZero)
+        return temMALFORMED;
+
     bool const bImmediateOrCancel(tx.isFlag(tfImmediateOrCancel));
     bool const bFillOrKill(tx.isFlag(tfFillOrKill));
 

src/libxrpl/tx/transactors/payment/Payment.cpp

@@ -125,6 +125,12 @@ Payment::preflight(PreflightContext const& ctx)
     if (!mpTokensV2 && isDstMPT && ctx.tx.isFieldPresent(sfPaths))
         return temMALFORMED;
 
+    // A zero DomainID is invalid for a PermissionedDomain ledger entry because
+    // keylet::permissionedDomain(uint256) uses the DomainID as the ledger key.
+    if (auto const domainID = tx[~sfDomainID];
+        ctx.rules.enabled(fixCleanup3_2_0) && domainID && *domainID == beast::kZero)
+        return temMALFORMED;
+
     bool const partialPaymentAllowed = tx.isFlag(tfPartialPayment);
     bool const limitQuality = tx.isFlag(tfLimitQuality);
     bool const defaultPathsAllowed = !tx.isFlag(tfNoRippleDirect);

src/test/app/PermissionedDEX_test.cpp

@@ -197,6 +197,20 @@ class PermissionedDEX_test : public beast::unit_test::Suite
             env.close();
         }
 
+        // test preflight - malformed DomainID being zero
+        // Only test this with fixCleanup3_2_0 enabled. Without the fix,
+        // an assert-enabled build can crash when Ledger::read() receives
+        // a zero-key PermissionedDomain keylet.
+        if (features[fixCleanup3_2_0])
+        {
+            Env env(*this, features);
+            auto const& [gw_, domainOwner, alice_, bob_, carol_, USD, domainID, credType] =
+                PermissionedDEX(env);
+
+            env(offer(bob_, XRP(10), USD(10)), Domain(uint256{}), Ter(temMALFORMED));
+            env.close();
+        }
+
         // preclaim - someone outside of the domain cannot create domain offer
         {
             Env env(*this, features);
@@ -396,6 +410,24 @@ class PermissionedDEX_test : public beast::unit_test::Suite
             env.close();
         }
 
+        // test preflight - malformed DomainID being zero
+        // Only test this with fixCleanup3_2_0 enabled. Without the fix,
+        // an assert-enabled build can crash when Ledger::read() receives
+        // a zero-key PermissionedDomain keylet.
+        if (features[fixCleanup3_2_0])
+        {
+            Env env(*this, features);
+            auto const& [gw_, domainOwner, alice_, bob_, carol_, USD, domainID, credType] =
+                PermissionedDEX(env);
+
+            env(pay(bob_, alice_, USD(10)),
+                Path(~USD),
+                Sendmax(XRP(10)),
+                Domain(uint256{}),
+                Ter(temMALFORMED));
+            env.close();
+        }
+
         // preclaim - cannot send payment with non existent domain
         {
             Env env(*this, features);
@@ -1772,7 +1804,9 @@ public:
 
         // Test domain offer (w/o hybrid)
         testOfferCreate(all);
+        testOfferCreate(all - fixCleanup3_2_0);
         testPayment(all);
+        testPayment(all - fixCleanup3_2_0);
         testBookStep(all);
         testRippling(all);
         testOfferTokenIssuerInDomain(all);

src/test/app/SHAMapStore_test.cpp

@@ -520,6 +520,25 @@ public:
         /////////////////////////////////////////////////////////////
         // Create NodeStore with two backends to allow online deletion of data.
         // Normally, SHAMapStoreImp handles all these details.
+        auto nscfg = env.app().config().section(ConfigSection::nodeDatabase());
+
+        // Provide default values.
+        if (!nscfg.exists("cache_size"))
+        {
+            nscfg.set(
+                "cache_size",
+                std::to_string(
+                    env.app().config().getValueFor(SizedItem::TreeCacheSize, std::nullopt)));
+        }
+
+        if (!nscfg.exists("cache_age"))
+        {
+            nscfg.set(
+                "cache_age",
+                std::to_string(
+                    env.app().config().getValueFor(SizedItem::TreeCacheAge, std::nullopt)));
+        }
+
         NodeStoreScheduler scheduler(env.app().getJobQueue());
 
         std::string const writableDb = "write";
@@ -528,7 +547,6 @@ public:
         auto archiveBackend = makeBackendRotating(env, scheduler, archiveDb);
 
         static constexpr int kReadThreads = 4;
-        auto nscfg = env.app().config().section(ConfigSection::nodeDatabase());
         auto dbr = std::make_unique<NodeStore::DatabaseRotatingImp>(
             scheduler,
             kReadThreads,

src/xrpld/app/consensus/RCLConsensus.cpp

@@ -784,7 +784,7 @@ RCLConsensus::Adaptor::buildLCL(
 
     // Update fee computations based on accepted txs
     using namespace std::chrono_literals;
-    app_.getTxQ().processClosedLedger(app_, *built, roundTime > 5s);
+    app_.getTxQ().processClosedLedger(app_, *built, roundTime > 2500ms);
 
     // And stash the ledger in the ledger master
     if (ledgerMaster_.storeLedger(built))

src/xrpld/app/main/Application.cpp

@@ -998,6 +998,10 @@ public:
             JLOG(journal_.debug()) << "MasterTransaction sweep.  Size before: " << oldMasterTxSize
                                    << "; size after: " << masterTxCache.size();
         }
+        {
+            // Sweep NodeStore database cache(s), if enabled.
+            getNodeStore().sweep();
+        }
         {
             std::size_t const oldLedgerMasterCacheSize = getLedgerMaster().getFetchPackCacheSize();
 

src/xrpld/app/misc/SHAMapStoreImp.cpp

@@ -165,6 +165,22 @@ std::unique_ptr<NodeStore::Database>
 SHAMapStoreImp::makeNodeStore(int readThreads)
 {
     auto nscfg = app_.config().section(ConfigSection::nodeDatabase());
+
+    // Provide default values.
+    if (!nscfg.exists("cache_size"))
+    {
+        nscfg.set(
+            "cache_size",
+            std::to_string(app_.config().getValueFor(SizedItem::TreeCacheSize, std::nullopt)));
+    }
+
+    if (!nscfg.exists("cache_age"))
+    {
+        nscfg.set(
+            "cache_age",
+            std::to_string(app_.config().getValueFor(SizedItem::TreeCacheAge, std::nullopt)));
+    }
+
     std::unique_ptr<NodeStore::Database> db;
 
     if (deleteInterval_ != 0u)
@@ -254,6 +270,8 @@ SHAMapStoreImp::run()
     LedgerIndex lastRotated = stateDb_.getState().lastRotated;
     netOPs_ = &app_.getOPs();
     ledgerMaster_ = &app_.getLedgerMaster();
+    fullBelowCache_ = &(*app_.getNodeFamily().getFullBelowCache());
+    treeNodeCache_ = &(*app_.getNodeFamily().getTreeNodeCache());
 
     if (advisoryDelete_)
         canDelete_ = stateDb_.getCanDelete();
@@ -542,16 +560,16 @@ SHAMapStoreImp::clearCaches(LedgerIndex validatedSeq)
     // Also clear the FullBelowCache so its generation counter is bumped.
     // This prevents stale "full below" markers from persisting across
     // backend rotation/online deletion and interfering with SHAMap sync.
-    app_.getNodeFamily().getFullBelowCache()->clear();
+    fullBelowCache_->clear();
 }
 
 void
 SHAMapStoreImp::freshenCaches()
 {
-    if (freshenCache(*app_.getNodeFamily().getTreeNodeCache()))
+    if (freshenCache(*treeNodeCache_))
+        return;
+    if (freshenCache(app_.getMasterTransaction().getCache()))
         return;
-
-    freshenCache(app_.getMasterTransaction().getCache());
 }
 
 void

src/xrpld/app/misc/SHAMapStoreImp.h

@@ -7,6 +7,8 @@
 #include <xrpl/nodestore/Scheduler.h>
 #include <xrpl/rdb/DatabaseCon.h>
 #include <xrpl/server/State.h>
+#include <xrpl/shamap/FullBelowCache.h>
+#include <xrpl/shamap/TreeNodeCache.h>
 
 #include <atomic>
 #include <chrono>
@@ -93,6 +95,8 @@ private:
     // as of run() or before
     NetworkOPs* netOPs_ = nullptr;
     LedgerMaster* ledgerMaster_ = nullptr;
+    FullBelowCache* fullBelowCache_ = nullptr;
+    TreeNodeCache* treeNodeCache_ = nullptr;
 
     static constexpr auto kNodeStoreName = "NodeStore";
 

src/xrpld/consensus/ConsensusParms.h

@@ -59,10 +59,10 @@ struct ConsensusParms
     std::size_t const minConsensusPct = 80;
 
     //! The duration a ledger may remain idle before closing
-    std::chrono::milliseconds const ledgerIdleInterval = std::chrono::seconds{15};
+    std::chrono::milliseconds const ledgerIdleInterval = std::chrono::seconds{5};
 
     //! The number of seconds we wait minimum to ensure participation
-    std::chrono::milliseconds const ledgerMinConsensus = std::chrono::milliseconds{1950};
+    std::chrono::milliseconds const ledgerMinConsensus = std::chrono::milliseconds{1000};
 
     /** The maximum amount of time to spend pausing for laggards.
      *
@@ -73,7 +73,7 @@ struct ConsensusParms
     std::chrono::milliseconds const ledgerMaxConsensus = std::chrono::seconds{15};
 
     //! Minimum number of seconds to wait to ensure others have computed the LCL
-    std::chrono::milliseconds const ledgerMinClose = std::chrono::seconds{2};
+    std::chrono::milliseconds const ledgerMinClose = std::chrono::seconds{1};
 
     //! How often we check state or change positions
     std::chrono::milliseconds const ledgerGRANULARITY = std::chrono::seconds{1};
@@ -99,7 +99,7 @@ struct ConsensusParms
         twice the interval between proposals (0.7s) divided by
         the interval between mid and late consensus ([85-50]/100).
     */
-    std::chrono::milliseconds const avMinConsensusTime = std::chrono::seconds{5};
+    std::chrono::milliseconds const avMinConsensusTime = std::chrono::seconds{2};
 
     //------------------------------------------------------------------------------
     // Avalanche tuning

src/xrpld/core/Config.h

@@ -209,7 +209,7 @@ public:
 
     // Work queue limits
     int maxTransactions = 250;
-    static constexpr int kMaxJobQueueTx = 1000;
+    static constexpr int kMaxJobQueueTx = 100000;
     static constexpr int kMinJobQueueTx = 100;
 
     // Amendment majority time

src/xrpld/overlay/detail/ProtocolVersion.cpp

@@ -64,7 +64,7 @@ to_string(ProtocolVersion const& p)
 }
 
 std::vector<ProtocolVersion>
-parseProtocolVersions(std::string_view value)
+parseProtocolVersions(boost::beast::string_view const& value)
 {
     static boost::regex const kRE(
         "^"                        // start of line
@@ -131,7 +131,7 @@ negotiateProtocolVersion(std::vector<ProtocolVersion> const& versions)
 }
 
 std::optional<ProtocolVersion>
-negotiateProtocolVersion(std::string_view versions)
+negotiateProtocolVersion(boost::beast::string_view const& versions)
 {
     auto const them = parseProtocolVersions(versions);
 

src/xrpld/overlay/detail/ProtocolVersion.h

@@ -1,9 +1,10 @@
 #pragma once
 
+#include <boost/beast/core/string.hpp>
+
 #include <cstdint>
 #include <optional>
 #include <string>
-#include <string_view>
 #include <utility>
 #include <vector>
 
@@ -38,7 +39,7 @@ to_string(ProtocolVersion const& p);
           no duplicates and will be sorted in ascending protocol order.
 */
 std::vector<ProtocolVersion>
-parseProtocolVersions(std::string_view s);
+parseProtocolVersions(boost::beast::string_view const& s);
 
 /** Given a list of supported protocol versions, choose the one we prefer. */
 std::optional<ProtocolVersion>
@@ -46,7 +47,7 @@ negotiateProtocolVersion(std::vector<ProtocolVersion> const& versions);
 
 /** Given a list of supported protocol versions, choose the one we prefer. */
 std::optional<ProtocolVersion>
-negotiateProtocolVersion(std::string_view versions);
+negotiateProtocolVersion(boost::beast::string_view const& versions);
 
 /** The list of all the protocol versions we support. */
 std::string const&

src/xrpld/rpc/detail/ServerHandler.cpp

@@ -264,7 +264,7 @@ ServerHandler::onHandoff(
 static inline json::Output
 makeOutput(Session& session)
 {
-    return [&](std::string_view b) { session.write(b.data(), b.size()); };
+    return [&](boost::beast::string_view const& b) { session.write(b.data(), b.size()); };
 }
 
 static std::map<std::string, std::string>
@@ -564,14 +564,11 @@ ServerHandler::processSession(
         makeOutput(*session),
         coro,
         forwardedFor(session->request()),
-        [&]() -> std::string_view {
+        [&] {
             auto const iter = session->request().find("X-User");
             if (iter != session->request().end())
-            {
-                auto const& val = iter->value();
-                return std::string_view(val.data(), val.size());
-            }
-            return std::string_view{};
+                return iter->value();
+            return boost::beast::string_view{};
         }());
 
     if (beast::rfc2616::isKeepAlive(session->request()))