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How to disable tracing at runtime from the Linux kernel command line?




Dear Linux folks,


I am trying to reduce the boot time of a standard Linux distribution kernel. Currently, distributions – at least Debian und Ubuntu – enable function tracing.

```
CONFIG_FTRACE=y
CONFIG_FUNCTION_TRACER=y
CONFIG_FUNCTION_GRAPH_TRACER=y

CONFIG_EVENT_TRACING=y
```

This is great, as it makes it easy to use tracing to hunt down things holding up the boot. But it also skews the boot time quite a lot.

```
$ sudo dmesg
[…]
[ 0.318412] initcall init_graph_trace+0x0/0x64 returned 0 after 199218 usecs
[…]
[    1.770287] calling  event_trace_init+0x0/0x2c2 @ 1
[ 2.052871] initcall event_trace_init+0x0/0x2c2 returned 0 after 275942 usecs
[…]
```

Is there a way to disable tracing on the Linux kernel command line to disable tracing?


Kind regards,

Paul