External memory

Hello everyone,
I am using Beagle bone Black, which has 4GB of EMMC. when this EMMC is fully used then how we can extend the memory of the board to execute every operation?

Thanks and Regards,

SSD connected with a USB adapter.

Use fstab to map the drive.

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to extend on foxsquirrel’s comment, place the swap file on the SSD and increase to the size as ya need.
hope this helps,


thanks for your reply…
Can I install and use libraries to write programs? e.g. opencv, any other.

When you map a drive using the /etc/fstab file it operates transparently, it becomes another directory in the tree.
When editing the fstab file, open 2 terminals, one with nano and the open fstab to do the actual file edit. The other terminal open and ready to test that file BEFORE you close nano and reboot. Be sure to save before testing, do not close out the editor until the test is successful.
In the other terminal

$sudo mount -a

If it is successful nothing will be returned, if you have an error you must fix that before rebooting.

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can use SD Card for it.

yes, just much slower and lower life expectancy. if you don’t care to lose your data on the sdcard, then ok, else i would not recommend it.

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If memory is correct, some of the SSD’s we tested were getting upwards of 150 Mbs, its been a while since doing that on the USB port, it might be what ever the max spec is for the USB port. The SD card is around 35 on a good day.

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Thank you so much for your patience. I mounted an SD card and tried to install the library on it; it was installed, but it was located in the eMMC of the board. but need to install it on the SD card.

ya, USB 2.0 is slow, i’m doing an rsync right now to back up my NAS, RPI4 to BBB, both have SSD drives, average transfer rate is 40M to 45M, no UAS support with USB 2.0. i have some JMicron USB-SATA units, they only get about 34MB transfer.

anything you install with/for the OS will go where the OS is installed. the way to get around this is to overlay a directory from the sdcard/SSD, all new file would go to the overlay directory, thus increase your storage area. however if our sdcard goes bad or you pull it. your system maybe come unstable.
i’ll leave the research up to you on overlay/overlayFS configuration. it’s been about 5 year since i did it.