On 6/21/19 12:28 AM, Erik Josefsson wrote:
Hi David,
On 6/19/19 3:38 AM, David Christensen wrote:
The best way to answer your question regarding performance of a size N
SD card vs. a size 2*N SD card is to buy two cards and benchmark them
using your workload. Please publish your findings.
Please find my four (4) findings below or at
http://paste.debian.net/1088723
The only benchmark I know how to use is flashbench. But unfortunately I
don't know how to interpret the resulting data.
I would be immensely grateful for advise on which of the 4 cards to use.
The testing was simple. I have downloaded and put the same copy of the
redpill RC3 image from http://box.redpill.dk/nonfree/ onto each SD card,
then I have followed the instructions. Each card now has an "Extended
system" created by the command box-add-gui on the same machine.
Then I have installed aptitude, run update and upgrade and autoclean,
and then installed and run flashbench with parameters: flashbench -a
/dev/mmcblk0 --blocksize=1024
The four cards are:
MicroSD SanDisk Extreme PRO 64GB [3] XC II
MicroSD SanDisk Extreme PLUS 64GB [3] XC I V30 A2
MicroSD SanDisk Extreme PLUS 32GB [3] HC I V30 A1
MicroSD SanDisk Ultra 32GB [1] HC I (10) A1
I can send a picture of the cards off list if this is unclear.
So the question is, which card should I use for Teres-I ?
If there are further benchmarks or tests that could help determine which
SD card is the best, I'd be happy to run them.
Best regards.
//Erik
<snip>
I'm not familiar with flashbench. Every tool has a learning curve; it's
up to you to decide how much effort you want to put into it.
When I wrote "benchmark them using your workload", I was thinking
"install Debian, install your apps, run your apps, quantify what you
can". If you're doing command-line stuff, the 'time' built-in for Bash
can be very useful. But, it's also good to get a subjective feel for
the system on the various media -- does it lag? Does it stutter/
freeze? Does it crash?
I found that Debian and FreeBSD on SanDisk Ultra Fit 16 GB USB 3.0 flash
drives was "good enough" for headless servers, but stuttered/ froze for
interactive graphical desktop use (during disk I/O; especially writes).
I have since migrated to used 16 GB SSD's. (Does your target hardware
have a SATA port?)
David