Re: Question: SSD speed

From	"Thomas Schmitt" <scdbackup@gmx.net>
Newsgroups	linux.debian.user
Subject	Re: Question: SSD speed
Date	2020-10-08 12:00 +0200
Message-ID	<AXASm-2P3-17@gated-at.bofh.it> (permalink)
References	<AXzWi-2fS-9@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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Hi,

Hans wrote:
> > > Smartctl is telling me, that my ssd drive is 6Gb/sec
> > > capable, but the actual speed is only 1,5GB/sec.
> > > [...]
> > > The notebook is a little bit older, [...]

Andrei POPESCU wrote:
> You would have gotten much better answers by just specifying the exact
> notebook make and model.

... plus the original report lines from smartctl which tell you the speed
value.

Michael Stone wrote:
> > I'd assume it's confusion between bits and bytes. [...]
> > just write out bit or byte

Andrei POPESCU wrote:
> SI prefixes can also help... if you use them consistently.

It is a classic that programs talk mixed about GB and GiB while not clearly
distinguishing them. In general, users must keep the difference in mind when
they compare "GB" values from different programs.
See
  https://en.wikipedia.org/wiki/Mebibyte

Normally i use programmer's units: KiB, MiB, GiB, TiB. Meanwhile this habit
becomes questionable. What was a nice extra of 2.4 percent in the "kilobytes"
era became 4.9 percent with "mega", 7.4 with "giga", and 10 with "tera".
The merchants begin to cheat in the other direction. A 128 "GB" USB stick
might offer only 126 billion bytes a storage capacity.

But in this thread about SSD speed it was most confusing for me to read this:

Hans wrote:
> > And second: If the real transferrate is only 1,5Gbyte/sec, does this mean,
> > that the sata controller is not capable to higher transferrates

No existing SATA can deliver 1.5 gigabytes (+/- 7.4 percent).
So something is wrong in this statement and only original output from
exactly quoted program runs could tell what.

Have a nice day :)

Thomas

Thread

Question: SSD speed Hans <hans.ullrich@loop.de> - 2020-10-07 10:50 +0200
  Re: Question: SSD speed Georgi Naplatanov <gosho@oles.biz> - 2020-10-07 11:40 +0200
  Re: Question: SSD speed Steve McIntyre <steve@einval.com> - 2020-10-07 12:00 +0200
  Re: Question: SSD speed "Jeremy Nicoll" <jn.ml.dbn.25@letterboxes.org> - 2020-10-07 12:00 +0200
    Re: Question: SSD speed Sven Hartge <sven@svenhartge.de> - 2020-10-07 12:50 +0200
      Re: Question: SSD speed Michael Stone <mstone@debian.org> - 2020-10-07 15:10 +0200
        Re: Question: SSD speed Andrei POPESCU <andreimpopescu@gmail.com> - 2020-10-08 11:00 +0200
          Re: Question: SSD speed "Thomas Schmitt" <scdbackup@gmx.net> - 2020-10-08 12:00 +0200
            [SOLVED] Re: Question: SSD speed Hans <hans.ullrich@loop.de> - 2020-10-08 12:20 +0200
            Re: Question: SSD speed Michael Stone <mstone@debian.org> - 2020-10-08 15:20 +0200
              Re: Question: SSD speed "Thomas Schmitt" <scdbackup@gmx.net> - 2020-10-08 16:00 +0200
                Re: Question: SSD speed Michael Stone <mstone@debian.org> - 2020-10-08 16:20 +0200
                Re: Question: SSD speed Stefan Monnier <monnier@iro.umontreal.ca> - 2020-10-08 17:40 +0200
                Re: Question: SSD speed Michael Stone <mstone@debian.org> - 2020-10-08 17:50 +0200
                Re: Question: SSD speed Stefan Monnier <monnier@iro.umontreal.ca> - 2020-10-08 18:00 +0200
              Re: Question: SSD speed Leslie Rhorer <lesrhorer@att.net> - 2020-10-08 20:30 +0200
                Re: Question: SSD speed Dan Ritter <dsr@randomstring.org> - 2020-10-08 20:40 +0200
                Re: Question: SSD speed Michael Stone <mstone@debian.org> - 2020-10-08 21:20 +0200
                Re: Question: SSD speed Leslie Rhorer <lesrhorer@att.net> - 2020-10-09 02:00 +0200
                Re: Question: SSD speed Michael Stone <mstone@debian.org> - 2020-10-09 02:20 +0200
                Re: Question: SSD speed Leslie Rhorer <lesrhorer@att.net> - 2020-10-09 02:40 +0200
                Re: Question: SSD speed Stefan Monnier <monnier@iro.umontreal.ca> - 2020-10-09 00:20 +0200
                Re: Question: SSD speed Leslie Rhorer <lesrhorer@att.net> - 2020-10-09 02:20 +0200
                Re: Question: SSD speed Stefan Monnier <monnier@iro.umontreal.ca> - 2020-10-09 15:50 +0200
    Re: Question: SSD speed Alberto Sentieri <22t@tripolho.com> - 2020-10-07 13:30 +0200
      Re: Question: SSD speed "Jeremy Nicoll" <jn.ml.dbn.25@letterboxes.org> - 2020-10-07 14:50 +0200
        Re: Question: SSD speed Andrei POPESCU <andreimpopescu@gmail.com> - 2020-10-08 10:50 +0200
    Re: Question: SSD speed Hans <hans.ullrich@loop.de> - 2020-10-07 18:50 +0200
      Re: Question: SSD speed "Jeremy Nicoll" <jn.ml.dbn.25@letterboxes.org> - 2020-10-07 18:50 +0200
      Re: Question: SSD speed Andy Smith <andy@strugglers.net> - 2020-10-07 19:50 +0200
        [SOLVED] Re: Question: SSD speed Hans <hans.ullrich@loop.de> - 2020-10-07 20:00 +0200
        [SOLVED] Re: Question: SSD speed Hans <hans.ullrich@loop.de> - 2020-10-08 09:10 +0200
  Re: Question: SSD speed Andrei POPESCU <andreimpopescu@gmail.com> - 2020-10-08 11:00 +0200

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