Merge branch 'asio-uring-web-server' of https://github.com/ashvardanian/BenchmarkingTutorial into asio-uring-web-server

Author: ashvardanian

.vscode/settings.json

@@ -2,6 +2,7 @@
   "cSpell.words": [
     "absl",
     "Accorn",
+    "accum",
     "Adelstein",
     "Andreas",
     "ashvardanian",
@@ -42,6 +43,7 @@
     "Fedor",
     "Fugaku",
     "Giga",
+    "GMMA",
     "Goodput",
     "GOPS",
     "GPGPU",
@@ -51,6 +53,7 @@
     "HKSTU",
     "HMMA",
     "Ibireme",
+    "IMMA",
     "IOSQE",
     "JeanHeyd",
     "jemalloc",
@@ -109,6 +112,7 @@
     "sysfs",
     "taskset",
     "Tera",
+    "Threadblock",
     "TMUL",
     "Trettner",
     "Unbundling",

CMakeLists.txt

@@ -94,6 +94,12 @@ set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -w")
 set(CMAKE_FIND_LIBRARY_PREFIXES ";lib")
 find_package(BLAS REQUIRED)
 
+include(CheckFunctionExists)
+check_function_exists(openblas_set_num_threads LESS_SLOW_HAS_OPENBLAS_SET_NUM_THREADS)
+if(LESS_SLOW_HAS_OPENBLAS_SET_NUM_THREADS)
+    add_definitions(-DLESS_SLOW_HAS_OPENBLAS_SET_NUM_THREADS)
+endif()
+
 # GTest (required by Google Benchmark)
 FetchContent_Declare(
   GoogleTest

README.md

@@ -55,6 +55,7 @@ cd less_slow.cpp                                            # Change the directo
 
 sudo apt-get install build-essential cmake g++              # Install default build tools
 sudo apt-get install pkg-config liburing-dev                # Install liburing for kernel-bypass
+sudo apt-get install libopenblas-base                       # Install numerics libraries
 
 cmake -B build_release -D CMAKE_BUILD_TYPE=Release          # Generate the build files
 cmake --build build_release --config Release                # Build the project

less_slow.cpp

@@ -2634,14 +2634,18 @@ std::size_t parse_size_string(std::string const &str) {
 #pragma region Memory Bound Linear Algebra
 #include <cblas.h>
 /**
- *! OpenBLAS defines a `SIZE` macro for internal use, which conflicts with `fmt`
- *! and other code trying to use that name for variable names, so we must undefine it.
+ *  ! OpenBLAS defines a `SIZE` macro for internal use, which conflicts with `fmt`
+ *  ! and other code trying to use that name for variable names, so we must undefine it.
  */
 #undef SIZE
 
 template <typename scalar_type_>
 static void cblas_tops(bm::State &state) {
+    // ! Not all versions of OpenBLAS define the `openblas_set_num_threads`
+    // ! symbol, so we use CMake's `CheckFunctionExists` for that.
+#if defined(LESS_SLOW_HAS_OPENBLAS_SET_NUM_THREADS)
     openblas_set_num_threads(physical_cores());
+#endif
 
     // BLAS expects leading dimensions: `lda` = `ldb` = `ldc` = `n` for square inputs.
     std::size_t n = static_cast<std::size_t>(state.range(0));
@@ -4229,13 +4233,14 @@ yyjson_alc yyjson_wrap_arena_prepend(arena_t &arena) noexcept {
  */
 
 #if defined(__x86_64__) && defined(__linux__)
-#include <asm/prctl.h>   // `ARCH_ENABLE_TAGGED_ADDR`
 #include <sys/syscall.h> // `SYS_arch_prctl`
 static bool enable_pointer_tagging(unsigned long bits = 1) noexcept {
     // The argument is required number of tag bits.
     // It is rounded up to the nearest LAM mode that can provide it.
     // For now only LAM_U57 is supported, with 6 tag bits.
-    return syscall(SYS_arch_prctl, ARCH_ENABLE_TAGGED_ADDR, bits) == 0;
+    // ! This requires kernel 6.2 or newer.
+    int _ARCH_ENABLE_TAGGED_ADDR = 0x4002;
+    return syscall(SYS_arch_prctl, _ARCH_ENABLE_TAGGED_ADDR, bits) == 0;
 }
 #else
 static bool enable_pointer_tagging(unsigned long = 0) noexcept { return false; }
@@ -6459,7 +6464,8 @@ class rpc_uring55_client {
 static void rpc_uring55(bm::State &state, networking_route_t route, std::size_t batch_size, std::size_t packet_size) {
     auto [major, minor] = fetch_linux_kernel_version();
     if (major < 5 || (major == 5 && minor < 5)) {
-        std::string message = std::format("Kernel version {}.{} too old for io_uring 5.0 variant", major, minor);
+        std::string message = "Kernel version "s + std::to_string(major) + "."s + std::to_string(minor) +
+                              " too old for io_uring 5.5 variant"s;
         state.SkipWithError(message.c_str());
         return;
     }
@@ -6794,7 +6800,8 @@ class rpc_uring60_client {
 static void rpc_uring60(bm::State &state, networking_route_t route, std::size_t batch_size, std::size_t packet_size) {
     auto [major, minor] = fetch_linux_kernel_version();
     if (major < 6) {
-        std::string message = std::format("Kernel version {}.{} too old for io_uring 6.0 variant", major, minor);
+        std::string message = "Kernel version "s + std::to_string(major) + "."s + std::to_string(minor) +
+                              " too old for io_uring 6.0 variant"s;
         state.SkipWithError(message.c_str());
         return;
     }