1		i	synthesize instructions events
 2		b	synthesize branches events
 3		c	synthesize branches events (calls only)
 4		r	synthesize branches events (returns only)
 5		x	synthesize transactions events
 
 
 
 
 6		e	synthesize error events
 7		d	create a debug log
 8		g	synthesize a call chain (use with i or x)
 9		l	synthesize last branch entries (use with i or x)
 
10
11	The default is all events i.e. the same as --itrace=ibxe
 
12
13	In addition, the period (default 100000) for instructions events
14	can be specified in units of:
15
16		i	instructions
17		t	ticks
18		ms	milliseconds
19		us	microseconds
20		ns	nanoseconds (default)
21
22	Also the call chain size (default 16, max. 1024) for instructions or
23	transactions events can be specified.
24
25	Also the number of last branch entries (default 64, max. 1024) for
26	instructions or transactions events can be specified.

 1		i	synthesize instructions events
 2		b	synthesize branches events
 3		c	synthesize branches events (calls only)
 4		r	synthesize branches events (returns only)
 5		x	synthesize transactions events
 6		w	synthesize ptwrite events
 7		p	synthesize power events
 8		o	synthesize other events recorded due to the use
 9			of aux-output (refer to perf record)
10		e	synthesize error events
11		d	create a debug log
12		g	synthesize a call chain (use with i or x)
13		l	synthesize last branch entries (use with i or x)
14		s       skip initial number of events
15
16	The default is all events i.e. the same as --itrace=ibxwpe,
17	except for perf script where it is --itrace=ce
18
19	In addition, the period (default 100000, except for perf script where it is 1)
20	for instructions events can be specified in units of:
21
22		i	instructions
23		t	ticks
24		ms	milliseconds
25		us	microseconds
26		ns	nanoseconds (default)
27
28	Also the call chain size (default 16, max. 1024) for instructions or
29	transactions events can be specified.
30
31	Also the number of last branch entries (default 64, max. 1024) for
32	instructions or transactions events can be specified.
33
34	It is also possible to skip events generated (instructions, branches, transactions,
35	ptwrite, power) at the beginning. This is useful to ignore initialization code.
36
37	--itrace=i0nss1000000
38
39	skips the first million instructions.