In OSX, SD Card transfers can be painfully slow
Over the weekend, I was trying to experiment with some SD card images for the UDOO Board.
When copying a new image into my SD Card, I realized that I was getting a really ridiculous slow writing speed of 1MB/s. This means that an 7GB image will take 100+ minutes just to copy.
It didn’t feel right with me and doing some quick googling, I’ve found out that
if I’m doing a dd directly to /dev/diskX which is where the sdcard is normally
mounted, I’ll be subjected to this slow speed.
What I should had done is to dd to /dev/rdiskX instead.
The reason being is that /diskX is buffered in 4KB chunks. Meaning that a copy
to diskX will be buffered 4KB at a time. This slows down speeds massively.
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