Try to build with liburing by default. (#8322)

Summary:
By default, try to build with liburing. For make, if ROCKSDB_USE_IO_URING is not set, treat as 1, which means RocksDB will try to build with liburing. For cmake, add WITH_LIBURING to control it, with default on.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8322

Test Plan: Build using cmake and make.

Reviewed By: anand1976

Differential Revision: D28586498

fbshipit-source-id: cfd39159ab697f4b93a9293a59c07f839b1e7ed5

CMakeLists.txt

@@ -62,6 +62,7 @@ if(CCACHE_FOUND)
 endif(CCACHE_FOUND)
 
 option(WITH_JEMALLOC "build with JeMalloc" OFF)
+option(WITH_LIBURING "build with liburing" ON)
 option(WITH_SNAPPY "build with SNAPPY" OFF)
 option(WITH_LZ4 "build with lz4" OFF)
 option(WITH_ZLIB "build with zlib" OFF)
@@ -338,6 +339,22 @@ if (NOT BUILTIN_ATOMIC)
 endif()
 endif()
 
+if (WITH_LIBURING)
+  set(CMAKE_REQUIRED_FLAGS "-luring")
+  CHECK_CXX_SOURCE_COMPILES("
+#include <liburing.h>
+int main() {
+  struct io_uring ring;
+  io_uring_queue_init(1, &ring, 0);
+  return 0;
+}
+" HAS_LIBURING)
+  if (HAS_LIBURING)
+    add_definitions(-DROCKSDB_IOURING_PRESENT)
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -luring")
+  endif()
+endif()
+
 # Reset the required flags
 set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS})
 

HISTORY.md

@@ -36,6 +36,9 @@
 ### Default Option Change
 * When options.arena_block_size <= 0 (default value 0), still use writer_buffer_size / 8 but cap to 1MB. Too large alloation size might not be friendly to allocator and might cause performance issues in extreme cases.
 
+### Build
+* By default, try to build with liburing. For make, if ROCKSDB_USE_IO_URING is not set, treat as enable, which means RocksDB will try to build with liburing. Users can disable it with ROCKSDB_USE_IO_URING=0. For cmake, add WITH_LIBURING to control it, with default on.
+
 ## 6.20.0 (2021-04-16)
 ### Behavior Changes
 * `ColumnFamilyOptions::sample_for_compression` now takes effect for creation of all block-based tables. Previously it only took effect for block-based tables created by flush.

build_tools/build_detect_platform

@@ -175,7 +175,10 @@ case "$TARGET_OS" in
             PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS -latomic"
         fi
         PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS -lpthread -lrt -ldl"
-        if test $ROCKSDB_USE_IO_URING; then
+        if test -z "$ROCKSDB_USE_IO_URING"; then
+            ROCKSDB_USE_IO_URING=1
+        fi
+        if test "$ROCKSDB_USE_IO_URING" -ne 0; then
             # check for liburing
             $CXX $PLATFORM_CXXFLAGS -x c++ - -luring -o /dev/null 2>/dev/null  <<EOF
               #include <liburing.h>