From 7e366a5ed302f15ee376826e18ab4da50281e6f6 Mon Sep 17 00:00:00 2001
From: Hung-Te Lin <hungte@chromium.org>
Date: Fri, 8 Oct 2010 10:35:10 +0800
Subject: [PATCH] crosutils: refine image_to_usb progress output and
 performance

Adding "-B 4m" to balance pipe (+10% speed on some SD) and -b to make progress more readable.
Since the size report from pv (k=1024) and dd(k=1000) are different, we also disable dd's summary report to prevent confusion.

BUG=none
TEST=executed: ./image_to_usb.sh --from=... --to=/dev/sdX (ok)

Change-Id: I184c4ce2d9a8274079ddb26f0420ccf8f2a674dd

Review URL: http://codereview.chromium.org/3608013
---
 image_to_usb.sh | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/image_to_usb.sh b/image_to_usb.sh
index 8248c393de..19eefb1f63 100755
--- a/image_to_usb.sh
+++ b/image_to_usb.sh
@@ -237,7 +237,10 @@ then
   if [ ${FLAGS_install} -ne ${FLAGS_TRUE} ]; then
     echo "Copying ${SRC_IMAGE} to ${FLAGS_to}..."
     if type pv >/dev/null 2>&1; then
-      sudo pv -ptre "${SRC_IMAGE}" | sudo dd of="${FLAGS_to}" bs=4M oflag=sync
+      # pv displays file size in k=1024 while dd uses k=1000.
+      # To prevent confusion, we suppress the summary report from dd.
+      sudo pv -ptreb -B 4m "${SRC_IMAGE}" |
+        sudo dd of="${FLAGS_to}" bs=4M oflag=sync status=noxfer
     else
       sudo dd if="${SRC_IMAGE}" of="${FLAGS_to}" bs=4M oflag=sync
     fi