Raspberry Pi SD Cards and the Raspberry Pi Bumper

raspberrypi.com

8 points·kaycebasques··7 comments

Some performance numbers would be better to understand what the real improvement is, SD / MicroSD card speeds vary a huge amount, even they are marked as the same class.

For example I was picking up an SD card for my camera, according to this test https://www.memorycard-lab.com/-Cameras/Panasonic-Lumix-S5-I...

There is a particular V60 card performs better than a lot of V90 cards.

https://www.raspberrypi.com/products/sd-cards/

Random 4KB read performance: 3,200 IOPS (Raspberry Pi 4, DDR50) 5,000 IOPS (Raspberry Pi 5, SDR104)

Random 4K write performance: 1,200 IOPS (Raspberry Pi 4, DDR50) 2,000 IOPS (Raspberry Pi 5, SDR104)

In my experience, sdcard support was a really black spot for rpi. With sdcards easily getting corrupted surprisingly contrary to when using alternative embedded boards like beaglebone.

So I'm not sure that I would trust them with an upgrade where async writing is used and that there is even more chances for corruption in case of bad condition like an unexpected shutdown.

There’s a whole section explaining how they mitigated that problem and tested it. They say «The Raspberry Pi kernel sidesteps this problem by limiting the maximum number of posted writes in CQ mode to one.»

That is the mitigation for the new CQ features. But still does not prove that sudden shutdown in the middle of a write or another command will not still kill or corrupt your sdcard like it used to do.

So are we taking bets on how long till the first counterfeit raspberry pi sd card shows up on amazon?

Sound good, but the performance numbers are a bit abstract for me. Any real world benchmarks?

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