mirror of
https://github.com/wezm/wezm.net.git
synced 2024-11-10 09:52:32 +00:00
153 lines
6.1 KiB
Markdown
153 lines
6.1 KiB
Markdown
|
+++
|
||
|
title = "Testing a $4 Micro SD Card From AliExpress"
|
||
|
date = 2024-04-07T15:06:25+10:00
|
||
|
|
||
|
#[extra]
|
||
|
#updated = 2024-02-21T10:05:19+10:00
|
||
|
+++
|
||
|
|
||
|
I needed three low capacity micro SD cards for an upcoming project. There's
|
||
|
plenty of these available on AliExpress but its very difficult to know if you
|
||
|
if the actual capacity will match the packaging. I did some research and came
|
||
|
across [this interesting video][video] that tested 16 different cards. Their
|
||
|
recommendation was the Lexar ones. So I found [some 32Gb ones for
|
||
|
AU$4.13][mycards] and placed an order[^1].
|
||
|
|
||
|
{{ figure(image="posts/2024/testing-aliexpress-sdcards/lexar-32gb-micro-sd-card.jpg", link="posts/2024/testing-aliexpress-sdcards/lexar-32gb-micro-sd-card.jpg", alt="Photo of the micro SD card in its packaging.", caption="The card being tested.", resize_width=880, width=440) }}
|
||
|
|
||
|
As per the video's suggestion I tested one with an open-source tool called
|
||
|
[F3 (Fight Flash Fraud)][f3] when they arrived. F3 verifies the capacity against
|
||
|
what the drive advertises and verifies that that amount of data can be written
|
||
|
and read back without error.
|
||
|
|
||
|
<!-- more -->
|
||
|
|
||
|
The card passed all tests. The packaging said up to 100MB/s read and is marked
|
||
|
C10/U1/V10, which is minimum 10MB/s sequential write. The tests showed a
|
||
|
write speed of 30.7MB/s and a read speed of 90.9MB/s, which feels within the
|
||
|
values advertised.
|
||
|
|
||
|
No idea what the endurance of the flash memory will end up being but I intend
|
||
|
to use them in a low-write environment, where failure doesn't really matter. If
|
||
|
the data the cards was storing was not easily replaced, such as photos, I
|
||
|
would still purchase from a repeatable local seller. However, for holding an
|
||
|
operating system image for a non-critical single board computer these seem
|
||
|
fine.
|
||
|
|
||
|
### Full Results
|
||
|
|
||
|
```
|
||
|
$ doas f3probe --destructive --time-ops /dev/sde
|
||
|
F3 probe 8.0
|
||
|
Copyright (C) 2010 Digirati Internet LTDA.
|
||
|
This is free software; see the source for copying conditions.
|
||
|
|
||
|
WARNING: Probing normally takes from a few seconds to 15 minutes, but
|
||
|
it can take longer. Please be patient.
|
||
|
|
||
|
Good news: The device `/dev/sde' is the real thing
|
||
|
|
||
|
Device geometry:
|
||
|
*Usable* size: 29.54 GB (61952000 blocks)
|
||
|
Announced size: 29.54 GB (61952000 blocks)
|
||
|
Module: 32.00 GB (2^35 Bytes)
|
||
|
Approximate cache size: 0.00 Byte (0 blocks), need-reset=no
|
||
|
Physical block size: 512.00 Byte (2^9 Bytes)
|
||
|
|
||
|
Probe time: 1'02"
|
||
|
Operation: total time / count = avg time
|
||
|
Read: 347.8ms / 4815 = 72us
|
||
|
Write: 1'02" / 4192321 = 14us
|
||
|
Reset: 0us / 1 = 0us
|
||
|
|
||
|
$ f3write /run/media/wmoore/8BF0-E09E/
|
||
|
F3 write 8.0
|
||
|
Copyright (C) 2010 Digirati Internet LTDA.
|
||
|
This is free software; see the source for copying conditions.
|
||
|
|
||
|
Free space: 29.53 GB
|
||
|
Creating file 1.h2w ... OK!
|
||
|
Creating file 2.h2w ... OK!
|
||
|
Creating file 3.h2w ... OK!
|
||
|
Creating file 4.h2w ... OK!
|
||
|
Creating file 5.h2w ... OK!
|
||
|
Creating file 6.h2w ... OK!
|
||
|
Creating file 7.h2w ... OK!
|
||
|
Creating file 8.h2w ... OK!
|
||
|
Creating file 9.h2w ... OK!
|
||
|
Creating file 10.h2w ... OK!
|
||
|
Creating file 11.h2w ... OK!
|
||
|
Creating file 12.h2w ... OK!
|
||
|
Creating file 13.h2w ... OK!
|
||
|
Creating file 14.h2w ... OK!
|
||
|
Creating file 15.h2w ... OK!
|
||
|
Creating file 16.h2w ... OK!
|
||
|
Creating file 17.h2w ... OK!
|
||
|
Creating file 18.h2w ... OK!
|
||
|
Creating file 19.h2w ... OK!
|
||
|
Creating file 20.h2w ... OK!
|
||
|
Creating file 21.h2w ... OK!
|
||
|
Creating file 22.h2w ... OK!
|
||
|
Creating file 23.h2w ... OK!
|
||
|
Creating file 24.h2w ... OK!
|
||
|
Creating file 25.h2w ... OK!
|
||
|
Creating file 26.h2w ... OK!
|
||
|
Creating file 27.h2w ... OK!
|
||
|
Creating file 28.h2w ... OK!
|
||
|
Creating file 29.h2w ... OK!
|
||
|
Creating file 30.h2w ... OK!
|
||
|
Free space: 0.00 Byte
|
||
|
Average writing speed: 30.71 MB/s
|
||
|
|
||
|
$ f3read /run/media/wmoore/8BF0-E09E/
|
||
|
F3 read 8.0
|
||
|
Copyright (C) 2010 Digirati Internet LTDA.
|
||
|
This is free software; see the source for copying conditions.
|
||
|
|
||
|
SECTORS ok/corrupted/changed/overwritten
|
||
|
Validating file 1.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 2.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 3.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 4.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 5.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 6.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 7.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 8.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 9.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 10.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 11.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 12.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 13.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 14.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 15.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 16.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 17.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 18.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 19.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 20.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 21.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 22.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 23.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 24.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 25.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 26.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 27.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 28.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 29.h2w ... 2097152/ 0/ 0/ 0
|
||
|
Validating file 30.h2w ... 1102208/ 0/ 0/ 0
|
||
|
|
||
|
Data OK: 29.53 GB (61919616 sectors)
|
||
|
Data LOST: 0.00 Byte (0 sectors)
|
||
|
Corrupted: 0.00 Byte (0 sectors)
|
||
|
Slightly changed: 0.00 Byte (0 sectors)
|
||
|
Overwritten: 0.00 Byte (0 sectors)
|
||
|
Average reading speed: 90.93 MB/s
|
||
|
```
|
||
|
|
||
|
[^1]: While these were branded Lexar there's really no way to know when ordering if they are
|
||
|
genuine or not. The main thing I care about is whether they hold as much data as they say.
|
||
|
|
||
|
[f3]: https://github.com/AltraMayor/f3
|
||
|
[video]: https://www.youtube.com/watch?v=efwDleEJY2w
|
||
|
[mycards]: https://www.aliexpress.com/item/1005005956657740.html
|