<s>
The	O
Linux	B-Application
Trace	I-Application
Toolkit	I-Application
(	O
LTT	O
)	O
is	O
a	O
set	O
of	O
tools	O
that	O
is	O
designed	O
to	O
log	O
program	O
execution	O
details	O
from	O
a	O
patched	O
Linux	O
kernel	O
and	O
then	O
perform	O
various	O
analyses	O
on	O
them	O
,	O
using	O
console-based	O
and	O
graphical	O
tools	O
.	O
</s>
<s>
LTT	O
has	O
been	O
mostly	O
superseded	O
by	O
its	O
successor	O
LTTng	B-Application
(	O
Linux	B-Application
Trace	I-Application
Toolkit	I-Application
Next	O
Generation	O
)	O
.	O
</s>
<s>
LTT	O
allows	O
the	O
user	O
to	O
see	O
in-depth	O
information	O
about	O
the	O
processes	O
that	O
were	O
running	O
during	O
the	O
trace	O
period	O
,	O
including	O
when	O
context	B-Operating_System
switches	I-Operating_System
occurred	O
,	O
how	O
long	O
the	O
processes	O
were	O
blocked	O
for	O
,	O
and	O
how	O
much	O
time	O
the	O
processes	O
spent	O
executing	O
vs.	O
how	O
much	O
time	O
the	O
processes	O
were	O
blocked	O
.	O
</s>
<s>
The	O
data	O
is	O
logged	O
to	O
a	O
text	O
file	O
and	O
various	O
console-based	O
and	O
graphical	O
(	O
GTK+	B-Application
)	O
tools	O
are	O
provided	O
for	O
interpreting	O
that	O
data	O
.	O
</s>
<s>
This	O
command	O
will	O
launch	O
a	O
graphical	O
(	O
GTK+	B-Application
)	O
traceview	O
tool	O
that	O
will	O
read	O
from	O
foo.trace	O
and	O
foo.proc	O
.	O
</s>
<s>
The	O
Event	O
Graph	O
is	O
perhaps	O
the	O
most	O
interesting	O
view	O
,	O
showing	O
the	O
exact	O
timing	O
of	O
events	O
like	O
page	B-General_Concept
faults	I-General_Concept
,	O
interrupts	B-Application
,	O
and	O
context	B-Operating_System
switches	I-Operating_System
,	O
in	O
a	O
simple	O
graphical	O
way	O
.	O
</s>
