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A2-class microSD cards offer no better performance for the Raspberry Pi

jeffgeerling.com

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Re: A2-class microSD cards offer no better performance for the Raspberry Pi

#71

Post by HankB99 »

JudgeWapner wrote: post #55
542458 wrote: post #52

Earlier quoted context omitted.

I didn’t even know you could do that! Any idea if it works on the pi4 or not? The docs don’t mention it. https://www.raspberrypi.org/documentation/hardware/raspberry...

just a guess but s/he may have been referring to just putting root filesystem on a USB drive, but still requiring the bootloader (and possibly kernel?) to be on sd card. It's a one-time "hit" that is completely negligible.

That's the present situation and I've used it before. Some recent Pis can boot directly from a USB drive without the need for a bootloader on the SD card. That's still in the works for the Pi 4 as I understand, but network boot (PXE?) will come before that.

Re: A2-class microSD cards offer no better performance for the Raspberry Pi

#72

Post by sebazzz »

rhardih wrote: post #63
jokoon wrote: post #45

How about lifespan? I fail to understand why SD card have such a short lifespan, and it's the sole reason I won't acquire an RPi. It seems that the only think that is lacking on RPi is flash memory storage. Most smartphones have a lot of it, and it seems that 1GB of storage would be enough for the RPi and would not necessarily be so expensive.

The Pi doesn't necessarily need an SD card. I'm running it on NFS, booted over the network. Works just fine. No need to worry about burning out the SD card.

What component supports NFS booting? The bootloader is on the SD card, right?

Re: A2-class microSD cards offer no better performance for the Raspberry Pi

#73

Post by Youden »

cameronbrown wrote: post #40
ggg3 wrote: post #37

sd card performance specs are all a joke. they are "at most" some speed. What even is the point of writting such spec? the car analogy would be if you measure some car going down a hill (doesn't even matter if tumbling and killing everyone inside), measuring that it was 300mph and then advertising it as "speeds of 300mph!!!"

Also how ISP speed is measured ;)

Advertised, not measured.

And it's not like that everywhere, the UK has started what I hope develops into a trend: https://www.bt.com/broadband/deals/

Re: A2-class microSD cards offer no better performance for the Raspberry Pi

#74

Post by oguzb »

jononor wrote: post #32
djsumdog wrote: post #18

I'm surprised we haven't seen a smaller than M.2 form factor for SATA on embedded devices. It seems like the big limiter on devices like the Raspberry Pi and others are the sd cards/emmc modules, since the amount processing power and ram have been continually going up. If you need disk performance on the Pi 4, wouldn't it make more sense to only keep the kernel,initrd on the sdcard and mount the primary filesystem of…

General practice in embedded is to avoid writing to disk as much as possible. Data collection is mostly done by sending it to the cloud for storage there. However 'edge processing' and 'edge storage' are hot topics, so there will probably be more work in this area. Some of the surveillance camera vendors are showing interest in this, since it would be beneficial to reduce data needed to be sent. Especially since vast…

Agreed, but Raspbian is not an embedded operating system. It spams the syslog and uses a journalling filesystem.

Re: A2-class microSD cards offer no better performance for the Raspberry Pi

#75

Post by 867-5309 »

megous wrote: post #36
dkersten wrote: post #11

Earlier quoted context omitted.

He explained in the article why he did this: to check if the manufacturers claims are incorrect, or if its a RPi hardware issue.

It's neither.

it's clearly the former.

Re: A2-class microSD cards offer no better performance for the Raspberry Pi

#76

Post by megous »

aidenn0 wrote: post #64
megous wrote: post #41

Earlier quoted context omitted.

I don't know. It's a bit of a bummer. I imagine Android would benefit the most (and phones also don't suffer from sudden power outages, which is the biggest risk with enabling this), so someone may try looking if mmc core in androind kernel has patches to support this.

My phone will reboot randomly; depending on what layer the reboot happens at, there may be no flush command sent to the card.

No worries, I checked it a few minutes ago, and android doesn't support this either.

Re: A2-class microSD cards offer no better performance for the Raspberry Pi

#78

Post by mbreese »

sebazzz wrote: post #72
rhardih wrote: post #63

Earlier quoted context omitted.

The Pi doesn't necessarily need an SD card. I'm running it on NFS, booted over the network. Works just fine. No need to worry about burning out the SD card.

What component supports NFS booting? The bootloader is on the SD card, right?

I believe the RPi can boot directly from the network, but it does require a one-time config change that requires booting from the SD card once. After that, the SD card isn’t required for future reboots.

(Or actually even supported, IIRC)

Re: A2-class microSD cards offer no better performance for the Raspberry Pi

#79

Post by [deleted] »

JudgeWapner wrote: post #55
542458 wrote: post #52

Earlier quoted context omitted.

I didn’t even know you could do that! Any idea if it works on the pi4 or not? The docs don’t mention it. https://www.raspberrypi.org/documentation/hardware/raspberry...

just a guess but s/he may have been referring to just putting root filesystem on a USB drive, but still requiring the bootloader (and possibly kernel?) to be on sd card. It's a one-time "hit" that is completely negligible.

[deleted]
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