How to judge whether the cache is shared or private?

Question

In general, l1 and l2 are private, and llc is shared. But I want to confirm if this is the case on my linux server. How can I know this information? The configuration of my server is as follows:

Linux version 4.15.0-122-generic (buildd@lcy01-amd64-010) (gcc version 5.4.0 20160609 (Ubuntu 5.4.0-6ubuntu1~16.04.12)) #124~16.04.1-Ubuntu SMP



lscpu --extend

CPU NODE SOCKET CORE L1d:L1i:L2:L3 ONLINE MAXMHZ    MINMHZ
0   0    0      0    0:0:0:0       是     2900.0000 1200.0000
1   1    1      1    1:1:1:1       是     2900.0000 1200.0000
2   0    0      2    2:2:2:0       是     2900.0000 1200.0000
3   1    1      3    3:3:3:1       是     2900.0000 1200.0000
4   0    0      4    4:4:4:0       是     2900.0000 1200.0000
5   1    1      5    5:5:5:1       是     2900.0000 1200.0000
6   0    0      6    6:6:6:0       是     2900.0000 1200.0000
7   1    1      7    7:7:7:1       是     2900.0000 1200.0000
8   0    0      8    8:8:8:0       是     2900.0000 1200.0000
9   1    1      9    9:9:9:1       是     2900.0000 1200.0000
10  0    0      10   10:10:10:0    是     2900.0000 1200.0000
11  1    1      11   11:11:11:1    是     2900.0000 1200.0000
12  0    0      12   12:12:12:0    是     2900.0000 1200.0000
13  1    1      13   13:13:13:1    是     2900.0000 1200.0000
14  0    0      14   14:14:14:0    是     2900.0000 1200.0000
15  1    1      15   15:15:15:1    是     2900.0000 1200.0000
16  0    0      16   16:16:16:0    是     2900.0000 1200.0000
17  1    1      17   17:17:17:1    是     2900.0000 1200.0000
18  0    0      18   18:18:18:0    是     2900.0000 1200.0000
19  1    1      19   19:19:19:1    是     2900.0000 1200.0000
20  0    0      20   20:20:20:0    是     2900.0000 1200.0000
21  1    1      21   21:21:21:1    是     2900.0000 1200.0000
22  0    0      22   22:22:22:0    是     2900.0000 1200.0000
23  1    1      23   23:23:23:1    是     2900.0000 1200.0000
24  0    0      0    0:0:0:0       是     2900.0000 1200.0000
25  1    1      1    1:1:1:1       是     2900.0000 1200.0000
26  0    0      2    2:2:2:0       是     2900.0000 1200.0000
27  1    1      3    3:3:3:1       是     2900.0000 1200.0000
28  0    0      4    4:4:4:0       是     2900.0000 1200.0000
29  1    1      5    5:5:5:1       是     2900.0000 1200.0000
30  0    0      6    6:6:6:0       是     2900.0000 1200.0000
31  1    1      7    7:7:7:1       是     2900.0000 1200.0000
32  0    0      8    8:8:8:0       是     2900.0000 1200.0000
33  1    1      9    9:9:9:1       是     2900.0000 1200.0000
34  0    0      10   10:10:10:0    是     2900.0000 1200.0000
35  1    1      11   11:11:11:1    是     2900.0000 1200.0000
36  0    0      12   12:12:12:0    是     2900.0000 1200.0000
37  1    1      13   13:13:13:1    是     2900.0000 1200.0000
38  0    0      14   14:14:14:0    是     2900.0000 1200.0000
39  1    1      15   15:15:15:1    是     2900.0000 1200.0000
40  0    0      16   16:16:16:0    是     2900.0000 1200.0000
41  1    1      17   17:17:17:1    是     2900.0000 1200.0000
42  0    0      18   18:18:18:0    是     2900.0000 1200.0000
43  1    1      19   19:19:19:1    是     2900.0000 1200.0000
44  0    0      20   20:20:20:0    是     2900.0000 1200.0000
45  1    1      21   21:21:21:1    是     2900.0000 1200.0000
46  0    0      22   22:22:22:0    是     2900.0000 1200.0000
47  1    1      23   23:23:23:1    是     2900.0000 1200.0000

Answer 1

It is right there in the fifth field.

• L1d level 1 data cache.
• L1i level 1 instruction cache.
• L2 level 2 cache.
• L3 level 3 (last level) cache.

Looking at the table, the L1 and L2 caches are private, but all the processors in a same socket (there are two sockets) share the same L3 cache.

The fact that the same information repeats indicates that you have a multithreading system.