OpenThread memory requirements

This page provides information about the layout and the amount of flash memory and RAM that is required by sample that are using the OpenThread stack. Use these values to see whether your application has enough space for running on particular platforms for different application configurations.

How to read the tables

The memory requirement tables list flash memory and RAM requirements for samples that were built using the available OpenThread pre-built libraries.

The values change depending on the sample, device type, and hardware platform. Moreover, take into account the following considerations:

• All samples were compiled using the default prj.conf, the overlay overlay-ot-defaults, and images from OpenThread pre-built libraries.

• The single protocol samples were optimized with the overlay overlay-minimal_singleprotocol.conf.

• The multiprotocol samples were optimized with the overlay overlay-minimal_multiprotocol.conf.

• To enable the multiprotocol support, the following options were used:

  • CONFIG_MPSL set to y (default setting for all samples)

  • CONFIG_BT_LL_SOFTDEVICE_DEFAULT set to y

  • CONFIG_BT set to y

  • CONFIG_BT_PERIPHERAL set to y

  • CONFIG_BT_DEVICE_NAME set to "NCS DUT"

  • CONFIG_BT_DEVICE_APPEARANCE set to 833

  • CONFIG_BT_MAX_CONN set to 1

• Values for the Thread CLI sample, which works with all OpenThread calls, are the highest possible for the OpenThread stack using the master image library configuration.

nRF52840 DK RAM and flash memory requirements

The following tables present memory requirements for samples running on the nRF52840 DK (nrf52840dk_nrf52840) with the hardware cryptography support provided by the CC310.

nRF52840 single protocol memory requirements

Sample	Variant	ROM OpenThread stack + App [kB]	ROM Bluetooth LE stack [kB]	Persistent storage [kB]	Free ROM [kB]	RAM OpenThread stack + App [kB]	RAM Bluetooth LE stack [kB]	Free RAM [kB]
CLI	master	398	0	32	594	81	0	175
CLI	ftd	379	0	32	613	80	0	176
CLI	mtd	322	0	32	670	72	0	184

nRF52840 multiprotocol memory requirements

Sample	Variant	ROM OpenThread stack + App [kB]	ROM Bluetooth LE stack [kB]	Persistent storage [kB]	Free ROM [kB]	RAM OpenThread stack + App [kB]	RAM Bluetooth LE stack [kB]	Free RAM [kB]
CLI	master	398	73	32	521	81	11	164
CLI	ftd	379	74	32	539	80	11	165
CLI	mtd	322	73	32	597	72	11	173

nRF52833 DK RAM and flash memory requirements

The following tables present memory requirements for samples running on the nRF52833 DK (nrf52833dk_nrf52833) with the software cryptography support provided by the nrf_oberon crypto library module.

nRF52833 single protocol memory requirements

Sample	Variant	ROM OpenThread stack + App [kB]	ROM Bluetooth LE stack [kB]	Persistent storage [kB]	Free ROM [kB]	RAM OpenThread stack + App [kB]	RAM Bluetooth LE stack [kB]	Free RAM [kB]
CLI	master	375	0	24	113	88	0	40
CLI	ftd	356	0	24	132	87	0	41
CLI	mtd	298	0	24	190	79	0	49

nRF52833 multiprotocol memory requirements

Sample	Variant	ROM OpenThread stack + App [kB]	ROM Bluetooth LE stack [kB]	Persistent storage [kB]	Free ROM [kB]	RAM OpenThread stack + App [kB]	RAM Bluetooth LE stack [kB]	Free RAM [kB]
CLI	master	375	74	24	39	88	11	29
CLI	ftd	356	74	24	58	87	11	30
CLI	mtd	298	74	24	116	79	11	38