Subject: bug#19544: RFE: please fix limited dd output control (want xfer stats, but not blocks).

From: Linda Walsh <[email-masked]>
Date: Fri, 09 Jan 2015 03:18:37 -0800

The blocks are a bit uninteresting:

7+0 records in
7+0 records out
6+0 records in
....

11+0 records out
8+0 records in
8+0 records out
2+0 records in
...
2+0 records out
15+0 records in
15+0 records out
---

Tells me nothing -- not size of recs, nor time.. nothing interesting.

What I'd rather see:

983040 bytes (983 KB) copied, 0.0135631 s, 72.5 MB/s
327680 bytes (328 KB) copied, 0.00869602 s, 37.7 MB/s
393216 bytes (393 KB) copied, 0.00978036 s, 40.2 MB/s
458752 bytes (459 KB) copied, 0.00906681 s, 50.6 MB/s
...
65536 bytes (66 KB) copied, 0.00843794 s, 7.8 MB/s
65536 bytes (66 KB) copied, 0.00845365 s, 7.8 MB/s
983040 bytes (983 KB) copied, 0.0128341 s, 76.6 MB/s
262144 bytes (262 KB) copied, 0.01019 s, 25.7 MB/s
262144 bytes (262 KB) copied, 0.00933135 s, 28.1 MB/s
589824 bytes (590 KB) copied, 0.0124597 s, 47.3 MB/s
1048576 bytes (1.0 MB) copied, 0.0138104 s, 75.9 MB/s
---

(Which, BTW, uses program intelligence to use the same output units as
the user used for input units, rather than giving them units in an
unfamiliar dialect).

Side note:
-----------

Which, BTW, is consistent using with use of other non-metric units, like
hours (you don't hear about kilo-hours or kilo-minutes) because the
units are not a multiple of 10 that is appropriate to use with Metric
prefixes).

I think the litmus test is whether or not the unit being used is some
power of
10 (and no arbitrary constant 'k' to convert it to a metric unit.

Thus bits, being a single, recognizable flux change on disk correspond
on a 1:1 basis (sans compression) to flux changes, and the number of
flux changes one can pack into a cm^2 is a pure calculation with base-10
metric units.  VS.  Speaking of 'Bytes', or Sectors, one is no longer
speaking of a direct metric unit, but of a convertible one.   It is rare
and not official practice to use metric prefixes with non Metric units.
As bytes are not a metric unit, using base-10 metric prefixes shouldn't
a point of discussion or contentions.  Bytes infer base-2 multiple
quantities that can only be precisely specified by base-2 prefixes.