Cleanup.

Author: trivialfis

src/common/io.cc

@@ -172,32 +172,21 @@ std::size_t GetPageSize() {
 #if defined(_MSC_VER)
   SYSTEM_INFO sys_info;
   GetSystemInfo(&sys_info);
-  // During testing, `sys_info.dwPageSize` is of size 4096 while `dwAllocationGranularity` is of size 65536.
+  // During testing, `sys_info.dwPageSize` is of size 4096 while `dwAllocationGranularity` is of
+  // size 65536.
   return sys_info.dwAllocationGranularity;
 #else
   return getpagesize();
 #endif
 }
 
-std::size_t PadPageForMmap(std::size_t file_bytes, dmlc::Stream* fo) {
-  decltype(file_bytes) page_size = GetPageSize();
-  CHECK(page_size != 0 && page_size % 2 == 0) << "Failed to get page size on the current system.";
-  CHECK_NE(file_bytes, 0) << "Empty page encountered.";
-  auto n_pages = file_bytes / page_size + !!(file_bytes % page_size != 0);
-  auto padded = n_pages * page_size;
-  auto padding = padded - file_bytes;
-  std::vector<std::uint8_t> padding_bytes(padding, 0);
-  // fo->Write(padding_bytes.data(), padding_bytes.size());
-  return file_bytes;
-}
-
 struct PrivateMmapStream::MMAPFile {
 #if defined(_MSC_VER)
-  HANDLE fd{ INVALID_HANDLE_VALUE };
+  HANDLE fd{INVALID_HANDLE_VALUE};
 #else
-  std::int32_t fd {0};
+  std::int32_t fd{0};
 #endif
-  char* base_ptr{ nullptr };
+  char* base_ptr{nullptr};
   std::size_t base_size{0};
   std::string path;
 };
@@ -255,7 +244,7 @@ char* PrivateMmapStream::Open(std::string path, bool read_only, std::size_t offs
   CHECK_NE(ptr, MAP_FAILED) << "Failed to map: " << path << ". " << strerror(errno);
 #endif  // defined(__linux__)
 
-  handle_.reset(new MMAPFile{ fd, ptr, view_size, std::move(path) });
+  handle_.reset(new MMAPFile{fd, ptr, view_size, std::move(path)});
   ptr += (offset - view_start);
   return ptr;
 }
@@ -272,7 +261,8 @@ PrivateMmapStream::~PrivateMmapStream() {
 #else
   CHECK_NE(munmap(handle_->base_ptr, handle_->base_size), -1)
       << "Faled to munmap." << handle_->path << ". " << strerror(errno);
-  CHECK_NE(close(handle_->fd), -1) << "Faled to close: " << handle_->path << ". " << strerror(errno);
+  CHECK_NE(close(handle_->fd), -1)
+      << "Faled to close: " << handle_->path << ". " << strerror(errno);
 #endif
 }
 }  // namespace common

src/common/io.h

@@ -130,15 +130,6 @@ inline std::string ReadAll(std::string const &path) {
 }
 
 std::size_t GetPageSize();
-/**
- * @brief Pad the output file for a page to make it mmap compatible.
- *
- * @param file_bytes The size of the output file
- * @param fo         Stream used to write the file.
- *
- * @return The file size after being padded.
- */
-std::size_t PadPageForMmap(std::size_t file_bytes, dmlc::Stream* fo);
 
 /**
  * @brief Private mmap file, copy-on-write. File must be properly aligned by `PadPageForMmap()`.

src/data/sparse_page_source.h

@@ -174,12 +174,11 @@ class SparsePageSourceImpl : public BatchIteratorImpl<S> {
     }
 
     auto bytes = fmt->Write(*page_, fo.get());
-    auto padded = common::PadPageForMmap(bytes, fo.get());
 
     timer.Stop();
     LOG(INFO) << static_cast<double>(bytes) / 1024.0 / 1024.0 << " MB written in "
               << timer.ElapsedSeconds() << " seconds.";
-    cache_info_->Push(padded);
+    cache_info_->Push(bytes);
   }
 
   virtual void Fetch() = 0;

tests/cpp/common/test_io.cc

@@ -111,8 +111,7 @@ TEST(IO, PrivateMmapStream) {
       fo->Write(data.data(), data.size() * sizeof(T));
 
       std::size_t bytes = sizeof(std::uint64_t) + data.size() * sizeof(T);
-      auto padded = common::PadPageForMmap(bytes, fo.get());
-      offset.push_back(padded);
+      offset.push_back(bytes);
 
       batches.emplace_back(std::move(data));
     }