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bug#17505: Interface inconsistency, use of intelligent defaults.
From: |
Linda Walsh |
Subject: |
bug#17505: Interface inconsistency, use of intelligent defaults. |
Date: |
Sat, 17 May 2014 01:23:20 -0700 |
User-agent: |
Thunderbird |
Paul Eggert wrote:
Linda Walsh wrote:
"125MB/s is literally impossible with a 1Gbit/s line - there will be
overhead"
This comment is using the usual powers-of-1000 abbreviations for both
the first figure (125 MB/s) and the second one (1 Gb/s), so it supports
the assertion that powers-of-1000 are more common in ordinary usage. 125
MB/s is impossible is because there is some overhead at lower protocol
levels, which means that you cannot possibly transfer 1 Gb of data over
a 1 Gb/s line in one second, i.e., you cannot possibly transfer 125 MB
of data over that line in one second, and that's what the comment says.
----
I see what you are saying, but having done that measurement myself,
I can assure you the 125MB/s is exactly what 'dd' reports (using direct
I/O). As I stated previously, when talking about bits, I see the decimal usage
as often as not. But when people talk about timings, they want to know how
long it will take to transfer the data on their disk -- given in base2 units
to 'X'...
Compare to 'ls', 'du', -- all give base2 units. If you think about
it the only way it would be "impossible" is if they though it was
125 * 2^20. But getting 125*10^6, is relatively trivial if your overhead is
< 1% -- dd won't show it. I could ask for clarification whether they were
using 2^20 or 10^6 for M. But 'dd' only requires that the overhead be less
than .4 or .5% to display 125.
- bug#17505: Interface inconsistency, use of intelligent defaults., Linda Walsh, 2014/05/15
- bug#17505: Interface inconsistency, use of intelligent defaults., Pádraig Brady, 2014/05/17
- bug#17505: Interface inconsistency, use of intelligent defaults., Paul Eggert, 2014/05/17
- bug#17505: Interface inconsistency, use of intelligent defaults., Pádraig Brady, 2014/05/17
- bug#17505: Interface inconsistency, use of intelligent defaults., Leslie Satenstein, 2014/05/17