Re: Understanding SD data transfer

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



What do you have it plugged into?  I have found some(most) of the
usb2/3/usbc claimed connected ones seem to run much slower.   You may
need some combination of lspci and lsusb to see how it is connected.

Note linux does not yet support UHS-II so any UHS-II card will run as
UHS-I until the kernel changes for MMC are done.


On Mon, Jul 24, 2023 at 5:44 PM Geoffrey Leach <geoffleach.gl@xxxxxxxxx> wrote:
>
> On Mon, 24 Jul 2023 14:53:15 -0700
> Samuel Sieb <samuel@xxxxxxxx> wrote:
>
> > On 7/24/23 14:44, Geoffrey Leach wrote:
> > > Fedora 37, up-to-date
> > > Controller JMicron Technology
> > > Medium 1TB SanDisk ultra SD, sped transfer rate 120MB/sec
> > > DATA 155MB
> > > df /Media/SDXC says its 26% full
> > >
> > > % mount /Media/SDXC
> > > % time cp DATA /Media/SDXC
> > > real                0m0.145s
> > > user                0m0.001s
> > > sys         0m0.41s
> > > % time cp DATA /Media/SDXC
> > > real                2m44.656s
> > > user                0m0.002s
> > > sys         0m0.211s
> > >
> > > I assume that the first cp just 'fills the queue, but  even assuming
> > > that I then have 310MB transferring, that's pretty slow.
> >
> > The SD card may support that speed, but the reader might not.  Try
> > running "iostat 1" in another window to see what the actual speeds
> > are.
>
> Hmmm .... well  iostat reports around 1  MB/sec, which is consistent
> with the data above. Not what I expected, given the specs on the card
> :-(
>
> Samuel, thanks.
> _______________________________________________
> users mailing list -- users@xxxxxxxxxxxxxxxxxxxxxxx
> To unsubscribe send an email to users-leave@xxxxxxxxxxxxxxxxxxxxxxx
> Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/
> List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines
> List Archives: https://lists.fedoraproject.org/archives/list/users@xxxxxxxxxxxxxxxxxxxxxxx
> Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
_______________________________________________
users mailing list -- users@xxxxxxxxxxxxxxxxxxxxxxx
To unsubscribe send an email to users-leave@xxxxxxxxxxxxxxxxxxxxxxx
Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/
List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines
List Archives: https://lists.fedoraproject.org/archives/list/users@xxxxxxxxxxxxxxxxxxxxxxx
Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue



[Index of Archives]     [Older Fedora Users]     [Fedora Announce]     [Fedora Package Announce]     [EPEL Announce]     [EPEL Devel]     [Fedora Magazine]     [Fedora Summer Coding]     [Fedora Laptop]     [Fedora Cloud]     [Fedora Advisory Board]     [Fedora Education]     [Fedora Security]     [Fedora Scitech]     [Fedora Robotics]     [Fedora Infrastructure]     [Fedora Websites]     [Anaconda Devel]     [Fedora Devel Java]     [Fedora Desktop]     [Fedora Fonts]     [Fedora Marketing]     [Fedora Management Tools]     [Fedora Mentors]     [Fedora Package Review]     [Fedora R Devel]     [Fedora PHP Devel]     [Kickstart]     [Fedora Music]     [Fedora Packaging]     [Fedora SELinux]     [Fedora Legal]     [Fedora Kernel]     [Fedora OCaml]     [Coolkey]     [Virtualization Tools]     [ET Management Tools]     [Yum Users]     [Yosemite News]     [Gnome Users]     [KDE Users]     [Fedora Art]     [Fedora Docs]     [Fedora Sparc]     [Libvirt Users]     [Fedora ARM]

  Powered by Linux