Merge branch 'develop' into ximinez/acquireAsyncDispatch

.github/workflows/pre-commit.yml

@@ -14,4 +14,4 @@ jobs:
     uses: XRPLF/actions/.github/workflows/pre-commit.yml@320be44621ca2a080f05aeb15817c44b84518108
     with:
       runs_on: ubuntu-latest
-      container: '{ "image": "ghcr.io/xrplf/ci/tools-rippled-pre-commit:sha-ab4d1f0" }'
+      container: '{ "image": "ghcr.io/xrplf/ci/tools-rippled-pre-commit:sha-41ec7c1" }'

.gitignore

@@ -42,6 +42,9 @@ gmon.out
 # Locally patched Conan recipes
 external/conan-center-index/
 
+# Local conan directory
+.conan
+
 # XCode IDE.
 *.pbxuser
 !default.pbxuser
@@ -72,5 +75,8 @@ DerivedData
 /.claude
 /CLAUDE.md
 
+# Direnv's directory
+/.direnv
+
 # clangd cache
 /.cache

.pre-commit-config.yaml

@@ -57,6 +57,16 @@ repos:
           - .git/COMMIT_EDITMSG
         stages: [commit-msg]
 
+  - repo: local
+    hooks:
+      - id: nix-fmt
+        name: Format Nix files
+        entry: nix --extra-experimental-features 'nix-command flakes' fmt
+        language: system
+        types:
+          - nix
+        pass_filenames: true
+
 exclude: |
   (?x)^(
       external/.*|

cspell.config.yaml

@@ -173,6 +173,9 @@ words:
   - nftokens
   - nftpage
   - nikb
+  - nixfmt
+  - nixos
+  - nixpkgs
   - nonxrp
   - noripple
   - nudb

docs/build/environment.md

@@ -3,6 +3,8 @@ environment complete with Git, Python, Conan, CMake, and a C++ compiler.
 This document exists to help readers set one up on any of the Big Three
 platforms: Linux, macOS, or Windows.
 
+As an alternative to system packages, the Nix development shell can be used to provide a development environment. See [using nix development shell](./nix.md) for more details.
+
 [BUILD.md]: ../../BUILD.md
 
 ## Linux

docs/build/nix.md

@@ -0,0 +1,95 @@
+# Using Nix Development Shell for xrpld Development
+
+This guide explains how to use Nix to set up a reproducible development environment for xrpld. Using Nix eliminates the need to manually install utilities and ensures consistent tooling across different machines.
+
+## Benefits of Using Nix
+
+- **Reproducible environment**: Everyone gets the same versions of tools and compilers
+- **No system pollution**: Dependencies are isolated and don't affect your system packages
+- **Multiple compiler versions**: Easily switch between different GCC and Clang versions
+- **Quick setup**: Get started with a single command
+- **Works on Linux and macOS**: Consistent experience across platforms
+
+## Install Nix
+
+Please follow [the official installation instructions of nix package manager](https://nixos.org/download/) for your system.
+
+## Entering the Development Shell
+
+### Basic Usage
+
+From the root of the xrpld repository, enter the default development shell:
+
+```bash
+nix --experimental-features 'nix-command flakes' develop
+```
+
+This will:
+
+- Download and set up all required development tools (CMake, Ninja, Conan, etc.)
+- Configure the appropriate compiler for your platform:
+  - **macOS**: Apple Clang (default system compiler)
+  - **Linux**: GCC 15
+
+The first time you run this command, it will take a few minutes to download and build the environment. Subsequent runs will be much faster.
+
+> [!TIP]
+> To avoid typing `--experimental-features 'nix-command flakes'` every time, you can permanently enable flakes by creating `~/.config/nix/nix.conf`:
+>
+> ```bash
+> mkdir -p ~/.config/nix
+> echo "experimental-features = nix-command flakes" >> ~/.config/nix/nix.conf
+> ```
+>
+> After this, you can simply use `nix develop` instead.
+
+> [!NOTE]
+> The examples below assume you've enabled flakes in your config. If you haven't, add `--experimental-features 'nix-command flakes'` after each `nix` command.
+
+### Choosing a different compiler
+
+A compiler can be chosen by providing its name with the `.#` prefix, e.g. `nix develop .#gcc15`.
+Use `nix flake show` to see all the available development shells.
+
+Use `nix develop .#no_compiler` to use the compiler from your system.
+
+### Example Usage
+
+```bash
+# Use GCC 14
+nix develop .#gcc14
+
+# Use Clang 19
+nix develop .#clang19
+
+# Use default for your platform
+nix develop
+```
+
+### Using a different shell
+
+`nix develop` opens bash by default. If you want to use another shell this could be done by adding `-c` flag. For example:
+
+```bash
+nix develop -c zsh
+```
+
+## Building xrpld with Nix
+
+Once inside the Nix development shell, follow the standard [build instructions](../../BUILD.md#steps). The Nix shell provides all necessary tools (CMake, Ninja, Conan, etc.).
+
+## Automatic Activation with direnv
+
+[direnv](https://direnv.net/) or [nix-direnv](https://github.com/nix-community/nix-direnv) can automatically activate the Nix development shell when you enter the repository directory.
+
+## Conan and Prebuilt Packages
+
+Please note that there is no guarantee that binaries from conan cache will work when using nix. If you encounter any errors, please use `--build '*'` to force conan to compile everything from source:
+
+```bash
+conan install .. --output-folder . --build '*' --settings build_type=Release
+```
+
+## Updating `flake.lock` file
+
+To update `flake.lock` to the latest revision use `nix flake update` command.

flake.lock

@@ -0,0 +1,26 @@
+{
+  "nodes": {
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1769461804,
+        "narHash": "sha256-6h5sROT/3CTHvzPy9koKBmoCa2eJKh4fzQK8eYFEgl8=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "b579d443b37c9c5373044201ea77604e37e748c8",
+        "type": "github"
+      },
+      "original": {
+        "id": "nixpkgs",
+        "ref": "nixos-unstable",
+        "type": "indirect"
+      }
+    },
+    "root": {
+      "inputs": {
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

flake.nix

@@ -0,0 +1,16 @@
+{
+  description = "Nix related things for xrpld";
+  inputs = {
+    nixpkgs.url = "nixpkgs/nixos-unstable";
+  };
+
+  outputs =
+    { nixpkgs, ... }:
+    let
+      forEachSystem = (import ./nix/utils.nix { inherit nixpkgs; }).forEachSystem;
+    in
+    {
+      devShells = forEachSystem (import ./nix/devshell.nix);
+      formatter = forEachSystem ({ pkgs, ... }: pkgs.nixfmt);
+    };
+}

include/xrpl/basics/MallocTrim.h

@@ -0,0 +1,73 @@
+#pragma once
+
+#include <xrpl/beast/utility/Journal.h>
+
+#include <chrono>
+#include <cstdint>
+#include <string_view>
+
+namespace xrpl {
+
+// cSpell:ignore ptmalloc
+
+// -----------------------------------------------------------------------------
+// Allocator interaction note:
+// - This facility invokes glibc's malloc_trim(0) on Linux/glibc to request that
+//   ptmalloc return free heap pages to the OS.
+// - If an alternative allocator (e.g. jemalloc or tcmalloc) is linked or
+//   preloaded (LD_PRELOAD), calling glibc's malloc_trim typically has no effect
+//   on the *active* heap. The call is harmless but may not reclaim memory
+//   because those allocators manage their own arenas.
+// - Only glibc sbrk/arena space is eligible for trimming; large mmap-backed
+//   allocations are usually returned to the OS on free regardless of trimming.
+// - Call at known reclamation points (e.g., after cache sweeps / online delete)
+//   and consider rate limiting to avoid churn.
+// -----------------------------------------------------------------------------
+
+struct MallocTrimReport
+{
+    bool supported{false};
+    int trimResult{-1};
+    std::int64_t rssBeforeKB{-1};
+    std::int64_t rssAfterKB{-1};
+    std::chrono::microseconds durationUs{-1};
+    std::int64_t minfltDelta{-1};
+    std::int64_t majfltDelta{-1};
+
+    [[nodiscard]] std::int64_t
+    deltaKB() const noexcept
+    {
+        if (rssBeforeKB < 0 || rssAfterKB < 0)
+            return 0;
+        return rssAfterKB - rssBeforeKB;
+    }
+};
+
+/**
+ * @brief Attempt to return freed memory to the operating system.
+ *
+ * On Linux with glibc malloc, this issues ::malloc_trim(0), which may release
+ * free space from ptmalloc arenas back to the kernel. On other platforms, or if
+ * a different allocator is in use, this function is a no-op and the report will
+ * indicate that trimming is unsupported or had no effect.
+ *
+ * @param tag     Identifier for logging/debugging purposes.
+ * @param journal Journal for diagnostic logging.
+ * @return Report containing before/after metrics and the trim result.
+ *
+ * @note If an alternative allocator (jemalloc/tcmalloc) is linked or preloaded,
+ *       calling glibc's malloc_trim may have no effect on the active heap. The
+ *       call is harmless but typically does not reclaim memory under those
+ *       allocators.
+ *
+ * @note Only memory served from glibc's sbrk/arena heaps is eligible for trim.
+ *       Large allocations satisfied via mmap are usually returned on free
+ *       independently of trimming.
+ *
+ * @note Intended for use after operations that free significant memory (e.g.,
+ *       cache sweeps, ledger cleanup, online delete). Consider rate limiting.
+ */
+MallocTrimReport
+mallocTrim(std::string_view tag, beast::Journal journal);
+
+}  // namespace xrpl

include/xrpl/protocol/detail/features.macro

@@ -15,9 +15,10 @@
 
 // Add new amendments to the top of this list.
 // Keep it sorted in reverse chronological order.
+
 XRPL_FIX   (PermissionedDomainInvariant, Supported::yes, VoteBehavior::DefaultNo)
 XRPL_FIX    (ExpiredNFTokenOfferRemoval, Supported::yes, VoteBehavior::DefaultNo)
-XRPL_FIX    (BatchInnerSigs,             Supported::yes, VoteBehavior::DefaultNo)
+XRPL_FIX    (BatchInnerSigs,             Supported::no, VoteBehavior::DefaultNo)
 XRPL_FEATURE(LendingProtocol,            Supported::yes, VoteBehavior::DefaultNo)
 XRPL_FEATURE(PermissionDelegationV1_1,   Supported::no,  VoteBehavior::DefaultNo)
 XRPL_FIX    (DirectoryLimit,             Supported::yes, VoteBehavior::DefaultNo)
@@ -31,7 +32,7 @@ XRPL_FEATURE(TokenEscrow,                Supported::yes, VoteBehavior::DefaultNo
 XRPL_FIX    (EnforceNFTokenTrustlineV2,  Supported::yes, VoteBehavior::DefaultNo)
 XRPL_FIX    (AMMv1_3,                    Supported::yes, VoteBehavior::DefaultNo)
 XRPL_FEATURE(PermissionedDEX,            Supported::yes, VoteBehavior::DefaultNo)
-XRPL_FEATURE(Batch,                      Supported::yes, VoteBehavior::DefaultNo)
+XRPL_FEATURE(Batch,                      Supported::no,  VoteBehavior::DefaultNo)
 XRPL_FEATURE(SingleAssetVault,           Supported::yes,  VoteBehavior::DefaultNo)
 XRPL_FIX    (PayChanCancelAfter,         Supported::yes, VoteBehavior::DefaultNo)
 // Check flags in Credential transactions

nix/devshell.nix

@@ -0,0 +1,140 @@
+{ pkgs, ... }:
+let
+  commonPackages = with pkgs; [
+    ccache
+    cmake
+    conan
+    gcovr
+    git
+    gnumake
+    llvmPackages_21.clang-tools
+    ninja
+    perl # needed for openssl
+    pkg-config
+    pre-commit
+    python314
+  ];
+
+  # Supported compiler versions
+  gccVersion = pkgs.lib.range 13 15;
+  clangVersions = pkgs.lib.range 18 21;
+
+  defaultCompiler = if pkgs.stdenv.isDarwin then "apple-clang" else "gcc";
+  defaultGccVersion = pkgs.lib.last gccVersion;
+  defaultClangVersion = pkgs.lib.last clangVersions;
+
+  strToCompilerEnv =
+    compiler: version:
+    (
+      if compiler == "gcc" then
+        let
+          gccPkg = pkgs."gcc${toString version}Stdenv" or null;
+        in
+        if gccPkg != null && builtins.elem version gccVersion then
+          gccPkg
+        else
+          throw "Invalid GCC version: ${toString version}. Must be one of: ${toString gccVersion}"
+      else if compiler == "clang" then
+        let
+          clangPkg = pkgs."llvmPackages_${toString version}".stdenv or null;
+        in
+        if clangPkg != null && builtins.elem version clangVersions then
+          clangPkg
+        else
+          throw "Invalid Clang version: ${toString version}. Must be one of: ${toString clangVersions}"
+      else if compiler == "apple-clang" || compiler == "none" then
+        pkgs.stdenvNoCC
+      else
+        throw "Invalid compiler: ${compiler}. Must be one of: gcc, clang, apple-clang, none"
+    );
+
+  # Helper function to create a shell with a specific compiler
+  makeShell =
+    {
+      compiler ? defaultCompiler,
+      version ? (
+        if compiler == "gcc" then
+          defaultGccVersion
+        else if compiler == "clang" then
+          defaultClangVersion
+        else
+          null
+      ),
+    }:
+    let
+      compilerStdEnv = strToCompilerEnv compiler version;
+
+      compilerName =
+        if compiler == "apple-clang" then
+          "clang"
+        else if compiler == "none" then
+          null
+        else
+          compiler;
+
+      gccOnMacWarning =
+        if pkgs.stdenv.isDarwin && compiler == "gcc" then
+          ''
+            echo "WARNING: Using GCC on macOS with Conan may not work."
+            echo "         Consider using 'nix develop .#clang' or the default shell instead."
+            echo ""
+          ''
+        else
+          "";
+
+      compilerVersion =
+        if compilerName != null then
+          ''
+            echo "Compiler: "
+            ${compilerName} --version
+          ''
+        else
+          ''
+            echo "No compiler specified - using system compiler"
+          '';
+
+      shellAttrs = {
+        packages = commonPackages;
+
+        shellHook = ''
+          echo "Welcome to xrpld development shell";
+          ${gccOnMacWarning}${compilerVersion}
+        '';
+      };
+    in
+    pkgs.mkShell.override { stdenv = compilerStdEnv; } shellAttrs;
+
+  # Generate shells for each compiler version
+  gccShells = builtins.listToAttrs (
+    map (version: {
+      name = "gcc${toString version}";
+      value = makeShell {
+        compiler = "gcc";
+        version = version;
+      };
+    }) gccVersion
+  );
+
+  clangShells = builtins.listToAttrs (
+    map (version: {
+      name = "clang${toString version}";
+      value = makeShell {
+        compiler = "clang";
+        version = version;
+      };
+    }) clangVersions
+  );
+
+in
+gccShells
+// clangShells
+// {
+  # Default shells
+  default = makeShell { };
+  gcc = makeShell { compiler = "gcc"; };
+  clang = makeShell { compiler = "clang"; };
+
+  # No compiler
+  no-compiler = makeShell { compiler = "none"; };
+  apple-clang = makeShell { compiler = "apple-clang"; };
+}

nix/utils.nix

@@ -0,0 +1,19 @@
+{ nixpkgs }:
+{
+  forEachSystem =
+    function:
+    nixpkgs.lib.genAttrs
+      [
+        "x86_64-linux"
+        "aarch64-linux"
+        "x86_64-darwin"
+        "aarch64-darwin"
+      ]
+      (
+        system:
+        function {
+          inherit system;
+          pkgs = import nixpkgs { inherit system; };
+        }
+      );
+}

src/libxrpl/basics/MallocTrim.cpp

@@ -0,0 +1,157 @@
+#include <xrpl/basics/Log.h>
+#include <xrpl/basics/MallocTrim.h>
+
+#include <boost/predef.h>
+
+#include <chrono>
+#include <cstdint>
+#include <cstdio>
+#include <fstream>
+#include <sstream>
+
+#if defined(__GLIBC__) && BOOST_OS_LINUX
+#include <sys/resource.h>
+
+#include <malloc.h>
+#include <unistd.h>
+
+// Require RUSAGE_THREAD for thread-scoped page fault tracking
+#ifndef RUSAGE_THREAD
+#error "MallocTrim rusage instrumentation requires RUSAGE_THREAD on Linux/glibc"
+#endif
+
+namespace {
+
+bool
+getRusageThread(struct rusage& ru)
+{
+    return ::getrusage(RUSAGE_THREAD, &ru) == 0;  // LCOV_EXCL_LINE
+}
+
+}  // namespace
+#endif
+
+namespace xrpl {
+
+namespace detail {
+
+// cSpell:ignore statm
+
+#if defined(__GLIBC__) && BOOST_OS_LINUX
+
+inline int
+mallocTrimWithPad(std::size_t padBytes)
+{
+    return ::malloc_trim(padBytes);
+}
+
+long
+parseStatmRSSkB(std::string const& statm)
+{
+    // /proc/self/statm format: size resident shared text lib data dt
+    // We want the second field (resident) which is in pages
+    std::istringstream iss(statm);
+    long size, resident;
+    if (!(iss >> size >> resident))
+        return -1;
+
+    // Convert pages to KB
+    long const pageSize = ::sysconf(_SC_PAGESIZE);
+    if (pageSize <= 0)
+        return -1;
+
+    return (resident * pageSize) / 1024;
+}
+
+#endif  // __GLIBC__ && BOOST_OS_LINUX
+
+}  // namespace detail
+
+MallocTrimReport
+mallocTrim(std::string_view tag, beast::Journal journal)
+{
+    // LCOV_EXCL_START
+
+    MallocTrimReport report;
+
+#if !(defined(__GLIBC__) && BOOST_OS_LINUX)
+    JLOG(journal.debug()) << "malloc_trim not supported on this platform (tag=" << tag << ")";
+#else
+    // Keep glibc malloc_trim padding at 0 (default): 12h Mainnet tests across 0/256KB/1MB/16MB
+    // showed no clear, consistent benefit from custom padding—0 provided the best overall balance
+    // of RSS reduction and trim-latency stability without adding a tuning surface.
+    constexpr std::size_t TRIM_PAD = 0;
+
+    report.supported = true;
+
+    if (journal.debug())
+    {
+        auto readFile = [](std::string const& path) -> std::string {
+            std::ifstream ifs(path, std::ios::in | std::ios::binary);
+            if (!ifs.is_open())
+                return {};
+
+            // /proc files are often not seekable; read as a stream.
+            std::ostringstream oss;
+            oss << ifs.rdbuf();
+            return oss.str();
+        };
+
+        std::string const tagStr{tag};
+        std::string const statmPath = "/proc/self/statm";
+
+        auto const statmBefore = readFile(statmPath);
+        long const rssBeforeKB = detail::parseStatmRSSkB(statmBefore);
+
+        struct rusage ru0{};
+        bool const have_ru0 = getRusageThread(ru0);
+
+        auto const t0 = std::chrono::steady_clock::now();
+
+        report.trimResult = detail::mallocTrimWithPad(TRIM_PAD);
+
+        auto const t1 = std::chrono::steady_clock::now();
+
+        struct rusage ru1{};
+        bool const have_ru1 = getRusageThread(ru1);
+
+        auto const statmAfter = readFile(statmPath);
+        long const rssAfterKB = detail::parseStatmRSSkB(statmAfter);
+
+        // Populate report fields
+        report.rssBeforeKB = rssBeforeKB;
+        report.rssAfterKB = rssAfterKB;
+        report.durationUs = std::chrono::duration_cast<std::chrono::microseconds>(t1 - t0);
+
+        if (have_ru0 && have_ru1)
+        {
+            report.minfltDelta = ru1.ru_minflt - ru0.ru_minflt;
+            report.majfltDelta = ru1.ru_majflt - ru0.ru_majflt;
+        }
+
+        std::int64_t const deltaKB = (rssBeforeKB < 0 || rssAfterKB < 0)
+            ? 0
+            : (static_cast<std::int64_t>(rssAfterKB) - static_cast<std::int64_t>(rssBeforeKB));
+
+        JLOG(journal.debug()) << "malloc_trim tag=" << tagStr << " result=" << report.trimResult
+                              << " pad=" << TRIM_PAD << " bytes"
+                              << " rss_before=" << rssBeforeKB << "kB"
+                              << " rss_after=" << rssAfterKB << "kB"
+                              << " delta=" << deltaKB << "kB"
+                              << " duration_us=" << report.durationUs.count()
+                              << " minflt_delta=" << report.minfltDelta
+                              << " majflt_delta=" << report.majfltDelta;
+    }
+    else
+    {
+        report.trimResult = detail::mallocTrimWithPad(TRIM_PAD);
+    }
+
+#endif
+
+    return report;
+
+    // LCOV_EXCL_STOP
+}
+
+}  // namespace xrpl

src/tests/libxrpl/basics/MallocTrim.cpp

@@ -0,0 +1,209 @@
+#include <xrpl/basics/MallocTrim.h>
+
+#include <boost/predef.h>
+
+#include <gtest/gtest.h>
+
+using namespace xrpl;
+
+// cSpell:ignore statm
+
+#if defined(__GLIBC__) && BOOST_OS_LINUX
+namespace xrpl::detail {
+long
+parseStatmRSSkB(std::string const& statm);
+}  // namespace xrpl::detail
+#endif
+
+TEST(MallocTrimReport, structure)
+{
+    // Test default construction
+    MallocTrimReport report;
+    EXPECT_EQ(report.supported, false);
+    EXPECT_EQ(report.trimResult, -1);
+    EXPECT_EQ(report.rssBeforeKB, -1);
+    EXPECT_EQ(report.rssAfterKB, -1);
+    EXPECT_EQ(report.durationUs, std::chrono::microseconds{-1});
+    EXPECT_EQ(report.minfltDelta, -1);
+    EXPECT_EQ(report.majfltDelta, -1);
+    EXPECT_EQ(report.deltaKB(), 0);
+
+    // Test deltaKB calculation - memory freed
+    report.rssBeforeKB = 1000;
+    report.rssAfterKB = 800;
+    EXPECT_EQ(report.deltaKB(), -200);
+
+    // Test deltaKB calculation - memory increased
+    report.rssBeforeKB = 500;
+    report.rssAfterKB = 600;
+    EXPECT_EQ(report.deltaKB(), 100);
+
+    // Test deltaKB calculation - no change
+    report.rssBeforeKB = 1234;
+    report.rssAfterKB = 1234;
+    EXPECT_EQ(report.deltaKB(), 0);
+}
+
+#if defined(__GLIBC__) && BOOST_OS_LINUX
+TEST(parseStatmRSSkB, standard_format)
+{
+    using xrpl::detail::parseStatmRSSkB;
+
+    // Test standard format: size resident shared text lib data dt
+    // Assuming 4KB page size: resident=1000 pages = 4000 KB
+    {
+        std::string statm = "25365 1000 2377 0 0 5623 0";
+        long result = parseStatmRSSkB(statm);
+        // Note: actual result depends on system page size
+        // On most systems it's 4KB, so 1000 pages = 4000 KB
+        EXPECT_GT(result, 0);
+    }
+
+    // Test with newline
+    {
+        std::string statm = "12345 2000 1234 0 0 3456 0\n";
+        long result = parseStatmRSSkB(statm);
+        EXPECT_GT(result, 0);
+    }
+
+    // Test with tabs
+    {
+        std::string statm = "12345\t2000\t1234\t0\t0\t3456\t0";
+        long result = parseStatmRSSkB(statm);
+        EXPECT_GT(result, 0);
+    }
+
+    // Test zero resident pages
+    {
+        std::string statm = "25365 0 2377 0 0 5623 0";
+        long result = parseStatmRSSkB(statm);
+        EXPECT_EQ(result, 0);
+    }
+
+    // Test with extra whitespace
+    {
+        std::string statm = "  25365   1000   2377  ";
+        long result = parseStatmRSSkB(statm);
+        EXPECT_GT(result, 0);
+    }
+
+    // Test empty string
+    {
+        std::string statm = "";
+        long result = parseStatmRSSkB(statm);
+        EXPECT_EQ(result, -1);
+    }
+
+    // Test malformed data (only one field)
+    {
+        std::string statm = "25365";
+        long result = parseStatmRSSkB(statm);
+        EXPECT_EQ(result, -1);
+    }
+
+    // Test malformed data (non-numeric)
+    {
+        std::string statm = "abc def ghi";
+        long result = parseStatmRSSkB(statm);
+        EXPECT_EQ(result, -1);
+    }
+
+    // Test malformed data (second field non-numeric)
+    {
+        std::string statm = "25365 abc 2377";
+        long result = parseStatmRSSkB(statm);
+        EXPECT_EQ(result, -1);
+    }
+}
+#endif
+
+TEST(mallocTrim, without_debug_logging)
+{
+    beast::Journal journal{beast::Journal::getNullSink()};
+
+    MallocTrimReport report = mallocTrim("without_debug", journal);
+
+#if defined(__GLIBC__) && BOOST_OS_LINUX
+    EXPECT_EQ(report.supported, true);
+    EXPECT_GE(report.trimResult, 0);
+    EXPECT_EQ(report.durationUs, std::chrono::microseconds{-1});
+    EXPECT_EQ(report.minfltDelta, -1);
+    EXPECT_EQ(report.majfltDelta, -1);
+#else
+    EXPECT_EQ(report.supported, false);
+    EXPECT_EQ(report.trimResult, -1);
+    EXPECT_EQ(report.rssBeforeKB, -1);
+    EXPECT_EQ(report.rssAfterKB, -1);
+    EXPECT_EQ(report.durationUs, std::chrono::microseconds{-1});
+    EXPECT_EQ(report.minfltDelta, -1);
+    EXPECT_EQ(report.majfltDelta, -1);
+#endif
+}
+
+TEST(mallocTrim, empty_tag)
+{
+    beast::Journal journal{beast::Journal::getNullSink()};
+    MallocTrimReport report = mallocTrim("", journal);
+
+#if defined(__GLIBC__) && BOOST_OS_LINUX
+    EXPECT_EQ(report.supported, true);
+    EXPECT_GE(report.trimResult, 0);
+#else
+    EXPECT_EQ(report.supported, false);
+#endif
+}
+
+TEST(mallocTrim, with_debug_logging)
+{
+    struct DebugSink : public beast::Journal::Sink
+    {
+        DebugSink() : Sink(beast::severities::kDebug, false)
+        {
+        }
+        void
+        write(beast::severities::Severity, std::string const&) override
+        {
+        }
+        void
+        writeAlways(beast::severities::Severity, std::string const&) override
+        {
+        }
+    };
+
+    DebugSink sink;
+    beast::Journal journal{sink};
+
+    MallocTrimReport report = mallocTrim("debug_test", journal);
+
+#if defined(__GLIBC__) && BOOST_OS_LINUX
+    EXPECT_EQ(report.supported, true);
+    EXPECT_GE(report.trimResult, 0);
+    EXPECT_GE(report.durationUs.count(), 0);
+    EXPECT_GE(report.minfltDelta, 0);
+    EXPECT_GE(report.majfltDelta, 0);
+#else
+    EXPECT_EQ(report.supported, false);
+    EXPECT_EQ(report.trimResult, -1);
+    EXPECT_EQ(report.durationUs, std::chrono::microseconds{-1});
+    EXPECT_EQ(report.minfltDelta, -1);
+    EXPECT_EQ(report.majfltDelta, -1);
+#endif
+}
+
+TEST(mallocTrim, repeated_calls)
+{
+    beast::Journal journal{beast::Journal::getNullSink()};
+
+    // Call malloc_trim multiple times to ensure it's safe
+    for (int i = 0; i < 5; ++i)
+    {
+        MallocTrimReport report = mallocTrim("iteration_" + std::to_string(i), journal);
+
+#if defined(__GLIBC__) && BOOST_OS_LINUX
+        EXPECT_EQ(report.supported, true);
+        EXPECT_GE(report.trimResult, 0);
+#else
+        EXPECT_EQ(report.supported, false);
+#endif
+    }
+}

src/xrpld/app/main/Application.cpp

@@ -31,6 +31,7 @@
 #include <xrpld/shamap/NodeFamily.h>
 
 #include <xrpl/basics/ByteUtilities.h>
+#include <xrpl/basics/MallocTrim.h>
 #include <xrpl/basics/ResolverAsio.h>
 #include <xrpl/basics/random.h>
 #include <xrpl/beast/asio/io_latency_probe.h>
@@ -1053,6 +1054,8 @@ public:
                                     << "; size after: " << cachedSLEs_.size();
         }
 
+        mallocTrim("doSweep", m_journal);
+
         // Set timer to do another sweep later.
         setSweepTimer();
     }