Another useful tool from the likwid performance monitoring and benchmarking suite is likwid-topology. Provides thread (hyperthread), cache (L1, L2, L3) and NUMA (memory) topology together.

Output below shows my i7-4770S CPU is a 4-core hyperthreaded processor with a 32KB L1D cache, 256 KB L2 cache per core and a shared 8 MB L3 cache.

mev@popayan:~$ likwid-topology
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CPU name:	Intel(R) Core(TM) i7-4770S CPU @ 3.10GHz
CPU type:	Intel Core Haswell processor
CPU stepping:	3
********************************************************************************
Hardware Thread Topology
********************************************************************************
Sockets:		1
Cores per socket:	4
Threads per core:	2
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HWThread	Thread		Core		Socket		Available
0		0		0		0		*
1		0		1		0		*
2		0		2		0		*
3		0		3		0		*
4		1		0		0		*
5		1		1		0		*
6		1		2		0		*
7		1		3		0		*
--------------------------------------------------------------------------------
Socket 0:		( 0 4 1 5 2 6 3 7 )
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********************************************************************************
Cache Topology
********************************************************************************
Level:			1
Size:			32 kB
Cache groups:		( 0 4 ) ( 1 5 ) ( 2 6 ) ( 3 7 )
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Level:			2
Size:			256 kB
Cache groups:		( 0 4 ) ( 1 5 ) ( 2 6 ) ( 3 7 )
--------------------------------------------------------------------------------
Level:			3
Size:			8 MB
Cache groups:		( 0 4 1 5 2 6 3 7 )
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********************************************************************************
NUMA Topology
********************************************************************************
NUMA domains:		1
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Domain:			0
Processors:		( 0 4 1 5 2 6 3 7 )
Distances:		10
Free memory:		4592.59 MB
Total memory:		15726.3 MB
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