Adjust partition formatting and mount options

Format the root partition with the metadata_csum option

Format the boot partition with 4 sectors per cluster for a slight performance boost

Remove 'flush' mount option from the boot partition

export-image/prerun.sh

@@ -70,12 +70,12 @@ if [ "${NO_PRERUN_QCOW2}" = "0" ]; then
 	echo "/:     offset $ROOT_OFFSET, length $ROOT_LENGTH"
 
 	ROOT_FEATURES="^huge_file"
-	for FEATURE in metadata_csum 64bit; do
+	for FEATURE in 64bit; do
 	if grep -q "$FEATURE" /etc/mke2fs.conf; then
 		ROOT_FEATURES="^$FEATURE,$ROOT_FEATURES"
 	fi
 	done
-	mkdosfs -n boot -F 32 -v "$BOOT_DEV" > /dev/null
+	mkdosfs -n boot -F 32 -s 4 -v "$BOOT_DEV" > /dev/null
 	mkfs.ext4 -L rootfs -O "$ROOT_FEATURES" "$ROOT_DEV" > /dev/null
 
 	mount -v "$ROOT_DEV" "${ROOTFS_DIR}" -t ext4

export-noobs/00-release/files/partitions.json

@@ -3,7 +3,7 @@
         {
             "filesystem_type": "FAT",
             "label": "boot",
-            "mkfs_options": "-F 32",
+            "mkfs_options": "-F 32 -s 4",
             "partition_size_nominal": BOOT_NOM,
             "uncompressed_tarball_size": BOOT_SIZE,
             "want_maximised": false,

export-noobs/00-release/files/release_notes.txt

@@ -1,5 +1,7 @@
 UNRELEASED:
-  * 
+  * Format the root partition with the metadata_csum option
+  * Format the boot partition with 4 sectors per cluster for a slight performance boost
+  * Remove 'flush' mount option from the boot partition
 2022-04-04:
   * Default "pi” user has been removed; the first-boot wizard enforces the creation of a new user account
   * rename-user script added to allow existing users to be renamed by temporarily rebooting to cut-down first-boot wizard

scripts/qcow2_handling

@@ -109,8 +109,8 @@ load_qimage() {
 EOF
 				sync
 				kpartx -as $NBD_DEV
-				mkdosfs -n boot -F 32 -v $MAP_BOOT_DEV
-				mkfs.ext4 -L rootfs -O "^huge_file,^metadata_csum,^64bit" $MAP_ROOT_DEV
+				mkdosfs -n boot -F 32 -s 4 -v $MAP_BOOT_DEV
+				mkfs.ext4 -L rootfs -O "^huge_file,^64bit" $MAP_ROOT_DEV
 				sync
 			else
 				if [ ! -f "${WORK_DIR}/image-${PREV_STAGE}.qcow2" ]; then

stage1/01-sys-tweaks/files/fstab

@@ -1,3 +1,3 @@
 proc            /proc           proc    defaults          0       0
-BOOTDEV  /boot           vfat    defaults,flush    0       2
+BOOTDEV  /boot           vfat    defaults          0       2
 ROOTDEV  /               ext4    defaults,noatime  0       1