Max Read/Write MicroSd on RPI 4

  • Hi to everyone, I currently use a SANDISK microSD Ultra 32GB U1

    100Mb/s read and 20Mb/s write for my Raspberry pi 4 with LibreElec and it works fine but I was thinking to buy a faster micro sd card Samsung 64 GB Evo Plus U3, what's the maximum read/write speed of the slot on the Raspberry Pi 4?

    I will have noticable improvement of performance on LibreElec?Thanks for answers.

  • If you spend $$ on faster SD cards you may be able to empirically measure a minor speed bump and it might boot marginally quicker, but in practical terms you will not notice any real-world difference in performance. Save goes for USB3 SSD drives; they are quicker in certain tests but you're unlikely to notice much difference (and you need to hang the drive out the back of the board, which is ugly).

  • If you spend $$ on faster SD cards you may be able to empirically measure a minor speed bump and it might boot marginally quicker, but in practical terms you will not notice any real-world difference in performance.

    I currently don't know about SDCards, but some higher priced USB Stick (Sandisk Extreme Pro, the elder one's) do have TRIM, too.

    USB Sticks and I guess sdcards too getting slow over time.

    to reset to initial speed one need to full format (not "quick" under windows) them from time to time.

    I guess a good measurement (not the card only, but Kernel, equipment, USB/SDCard) would be:

    write speed:

    dd if=/dev/zero of=tempfile bs=1MB count=10240

    read speed:

    dd if=tempfile of=/dev/zero bs=1MB count=10240

    both with cd'ed to a folder on the USB/sdcard first !

    anyway for an 256 GB Samsung EVO Plus (SAMSUNG MB-MC256HA-EU) under Windows/Linux with an sdcard reader (Transend TS-RDF5) I get this: