fs: improve fsPromises writeFile performance

Linkgoron · danielleadams · commit ba91ef2d08f6 · 2021-03-16T12:31:39.000-04:00
Increase the write chunk size in fsPromises writeFile to improve performance. PR-URL: #37610 Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Darshan Sen <raisinten@gmail.com> Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com> Reviewed-By: Anna Henningsen <anna@addaleax.net> Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
diff --git a/lib/internal/fs/promises.js b/lib/internal/fs/promises.js
@@ -6,7 +6,7 @@ const kIoMaxLength = 2 ** 31 - 1;
 
 const kReadFileBufferLength = 512 * 1024;
 const kReadFileUnknownBufferLength = 64 * 1024;
-const kWriteFileMaxChunkSize = 2 ** 14;
+const kWriteFileMaxChunkSize = 512 * 1024;
 
 const {
   ArrayPrototypePush,
diff --git a/test/parallel/test-fs-promises-file-handle-writeFile.js b/test/parallel/test-fs-promises-file-handle-writeFile.js
@@ -30,7 +30,7 @@ async function validateWriteFile() {
 async function doWriteAndCancel() {
   const filePathForHandle = path.resolve(tmpDir, 'dogs-running.txt');
   const fileHandle = await open(filePathForHandle, 'w+');
-  const buffer = Buffer.from('dogs running'.repeat(10000), 'utf8');
+  const buffer = Buffer.from('dogs running'.repeat(512 * 1024), 'utf8');
   const controller = new AbortController();
   const { signal } = controller;
   process.nextTick(() => controller.abort());
