(09-29-2020, 03:58 PM)wdt Wrote: So it doesn't interrupt pipeline to ask password, sudo for xzcat is not neccessary,
but then won't ask password for sudo dd
mrfixit_update.sh not only updates uboot and kernel, also changes extlinux.conf to point to new kernel
For any other distro, this would not work out well Ok thanks.
I'll get blasted for this surely, but just don't use sudo. All your data should be backed up, because yes, dd can cause disaster with one errant keystroke in any case. Just be root. It makes this so much simpler. You don't have to log in as root, use `su` the old fashioned way. Be deliberate. Errors can be very costly.
bs=64k is repeatably the fastest of 16k, 32k, 64k, 128k, 256k, 512k, 1m, 2m, 4m, 8m, 16m on my PBP with the SD cards I use, running NetBSD-current 9.99.72. The SD card I use are the Sandisk cards that GoPro recommended for the Hero 3+. On my P4-based machine, 256k is fastest. On my fastest desktop machine, 8m and 16m fare very similar, as the fastest. Of course, your mileage will likely vary drastically.
(09-29-2020, 07:10 PM)KC9UDX Wrote: I'll get blasted for this surely, but just don't use sudo. All your data should be backed up, because yes, dd can cause disaster with one errant keystroke in any case. Just be root. It makes this so much simpler. You don't have to log in as root, use `su` the old fashioned way. Be deliberate. Errors can be very costly.
bs=64k is repeatably the fastest of 16k, 32k, 64k, 128k, 256k, 512k, 1m, 2m, 4m, 8m, 16m on my PBP with the SD cards I use, running NetBSD-current 9.99.72. The SD card I use are the Sandisk cards that GoPro recommended for the Hero 3+. On my P4-based machine, 256k is fastest. On my fastest desktop machine, 8m and 16m fare very similar, as the fastest. Of course, your mileage will likely vary drastically. For me as a noob that raises the question, if an application like etcher is basically a ui frontend that I assume essentially does exactly what you can do in terminal, what speed do applications set for sd cards?
09-29-2020, 09:45 PM
(This post was last modified: 09-29-2020, 09:57 PM by wdt.)
>what speed do applications set for sd cards?
This I know a bit about
Application does not set speed, it is an intereletion between hardware and drivers
And you NEVER reach the theoretical maximum
Normal speed, all cards 50mhz, nibbles, in real life ~23MB/s, not 25
If the card is capable, traces balanced, 1.8V capable, clock capable,, you may see
I think called sdr204, anyway 100+MB/s,, and you won't see that,
maybe close for reading large blocks (and there are other, lower frequencies, slower)
Writing is always worse, sometimes a lot worse
Run some iozone tests, you will see,, 4k and 16k particularly bad
And this last point is how to tell how bad the card is, poor to terrible
maybe someday we will see 3d-xpoint in cards, I'm not holding my breath
A quite good card, writing an image, dd bs=1M status=progress will be 40MB/s
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