Apple 3X108 manual Multicore Memory Tests

Test	Estimated completion time	Description
Random	45 seconds	Uses pseudo-random values.
Block Checkerboard 32	15 seconds	Alternates 32-bit words with all
		1s and all 0s, and then with all
		0s and all 1s.
Bit Checkerboard 32	15 seconds	Alternates bits with all 1s and
		all 0s, and then with all 0s and
		all 1s.
Sequential Byte Block 32	32 minutes	Fills bytes sequentially with
		patterns starting at 0x00 and
		ending at 0xFF.
Walking One 32	15 minutes	Walks 1s up and down memory.
Walking Zero 32	15 minutes	Walks 0s up and down memory.
Walking Spread Bit 32	15 minutes	Walks 0b01 up and then walks
		0b10 down memory.
Walking Bit Flip 32	15 minutes	Alternates words with walking
		1 and walking 0, and then
		alternates with walking 0 and
		walking 1.

Multicore Memory Tests

In Server Diagnostics EFI, all memory tests (simple, multicore, and extended) are grouped under Memory tests.

Note: The time required to complete memory tests correlates to the amount of memory being tested. These estimates are based on testing 8 GB of memory.

Test	Estimated completion time	Description
MP Block Checkerboard	10 seconds	Alternates 32-bit words with all
		1s and all 0s, and then with all
		0s and all 1s.
MP Bit Checkerboard	10 seconds	Alternates bits with all 1s and
		all 0s, and then with all 0s and
		all 1s.
MP Sequential Byte Block	16 minutes	Fills bytes sequentially with
		patterns starting at 0x00 and
		ending at 0xFF.
MP Walking One	7 minutes	Walks 1s up and down memory.
MP Walking Zero	7 minutes	Walks 0s up and down memory.
MP Walking Spread Bit	7 minutes	Walks 0b01 up and then walks
		0b10 down memory.

Appendix    Server Diagnostics Test Reference

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