Demonstrations of numasched.py, the Linux eBPF/bcc version.

This example trace the task switch numa. Some example output:

NUMA Information:

$ numactl --hardware

available: 4 nodes (0-3)

node 0 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

node 0 size: 97373 MB

node 0 free: 1756 MB

node 1 cpus: 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47

node 1 size: 98192 MB

node 1 free: 1269 MB

node 2 cpus: 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71

node 2 size: 98192 MB

node 2 free: 4811 MB

node 3 cpus: 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95

node 3 size: 98135 MB

node 3 free: 1617 MB

node distances:

node 0 1 2 3

0: 10 12 20 22

1: 12 10 22 24

2: 20 22 10 12

3: 22 24 12 10

Terminal 1, start a task running on NUMA0:

$ taskset -c 1 yes >/dev/null

Terminal 2, start tracing:

$ sudo ./numasched.py

Terminal 3

# taskset 'yes' task to NUMA1(cpu=24):

$ taskset -p 0x1000000 $(pidof yes)

# taskset 'yes' task to NUMA2(cpu=48):

$ taskset -p 0x1000000000000 $(pidof yes)

Then, Terminal 2 shows:

$ sudo ./numasched.py

Tracing task NUMA switch...

TIME PID TID SRC_NID DST_NID COMM

20:55:35 355842 355842 0 -> 1 b'yes'

20:55:50 355842 355842 1 -> 2 b'yes'