<s>
Instruments	O
(	O
formerly	O
Xray	B-Operating_System
)	O
is	O
an	O
application	O
performance	O
analyzer	O
and	O
visualizer	O
,	O
integrated	O
in	O
Xcode	B-Operating_System
3.0	I-Operating_System
and	O
later	O
versions	O
of	O
Xcode	B-Operating_System
.	O
</s>
<s>
It	O
is	O
built	O
on	O
top	O
of	O
the	O
DTrace	B-Application
tracing	O
framework	B-Architecture
from	O
OpenSolaris	B-Operating_System
,	O
which	O
was	O
ported	O
to	O
Mac	B-Application
OS	I-Application
X	I-Application
v10.5	I-Application
and	O
which	O
is	O
available	O
in	O
all	O
following	O
versions	O
of	O
macOS	B-Application
.	O
</s>
<s>
Instruments	O
shows	O
a	O
time	O
line	O
displaying	O
any	O
event	O
occurring	O
in	O
the	O
application	O
,	O
such	O
as	O
CPU	B-General_Concept
activity	O
variation	O
,	O
memory	O
allocation	O
,	O
and	O
network	O
and	O
file	B-Operating_System
activity	O
,	O
together	O
with	O
graphs	O
and	O
statistics	O
.	O
</s>
<s>
CPU	B-General_Concept
activity	O
of	O
processes	B-Operating_System
and	O
threads	B-Operating_System
.	O
</s>
<s>
Memory	O
allocation	O
and	O
release	O
,	O
garbage	B-General_Concept
collection	I-General_Concept
and	O
memory	B-Error_Name
leaks	I-Error_Name
.	O
</s>
<s>
File	B-Operating_System
reads	O
,	O
writes	O
,	O
locks	O
.	O
</s>
<s>
Graphics	O
and	O
inner	O
workings	O
of	O
OpenGL	B-Application
and	O
Metal	B-Library
.	O
</s>
<s>
User	O
events	O
,	O
such	O
as	O
keyboard	B-Device
keys	O
pressed	O
and	O
mouse	O
moves	O
and	O
clicks	O
with	O
exact	O
time	O
.	O
</s>
