Added file.sync_data() so the time reported is more accurate (#1)

Closes #1 and tracks the transfer time more accurate by flushing the kernel cache
sassman · Nov 10, 2020 · 94f7f22 · 94f7f22
1 parent 00af295
commit 94f7f22
Show file tree

Hide file tree

Showing 2 changed files with 33 additions and 30 deletions.
diff --git a/Cargo.lock b/Cargo.lock
diff --git a/src/main.rs b/src/main.rs
@@ -169,8 +169,13 @@ fn write_once(buffer: &[u8]) -> std::io::Result<Duration> {
         let mut file = File::create("test").expect("Can't open test file");
 
         for _ in 0..TOTAL_SIZE_MB / BUF_SIZE_MB {
-            write_time += prof! {
+            // make sure the data is synced with the disk as the kernel performs
+            // write buffering
+            //
+            // TODO Open the file in O_DSYNC instead to avoid the additional syscall
+            write_time += prof!{
                 file.write_all(buffer)?;
+                file.sync_data()?;
             };
             print!(".");
             stdout().flush()?;