<s>
Fast	B-General_Concept
path	I-General_Concept
is	O
a	O
term	O
used	O
in	O
computer	B-General_Concept
science	I-General_Concept
to	O
describe	O
a	O
path	O
with	O
shorter	O
instruction	B-General_Concept
path	I-General_Concept
length	I-General_Concept
through	O
a	O
program	O
compared	O
to	O
the	O
normal	O
path	O
.	O
</s>
<s>
For	O
a	O
fast	B-General_Concept
path	I-General_Concept
to	O
be	O
effective	O
it	O
must	O
handle	O
the	O
most	O
commonly	O
occurring	O
tasks	O
more	O
efficiently	O
than	O
the	O
normal	O
path	O
,	O
leaving	O
the	O
latter	O
to	O
handle	O
uncommon	O
cases	O
,	O
corner	O
cases	O
,	O
error	O
handling	O
,	O
and	O
other	O
anomalies	O
.	O
</s>
<s>
Fast	B-General_Concept
paths	I-General_Concept
are	O
a	O
form	O
of	O
optimization	O
.	O
</s>
<s>
For	O
example	O
dedicated	O
packet	B-Protocol
routing	I-Protocol
hardware	O
used	O
to	O
build	O
computer	B-Architecture
networks	I-Architecture
will	O
often	O
support	O
software	O
dedicated	O
to	O
handling	O
the	O
most	O
common	O
kinds	O
of	O
packets	O
,	O
with	O
other	O
kinds	O
,	O
for	O
example	O
with	O
control	O
information	O
or	O
packets	O
directed	O
at	O
the	O
device	O
itself	O
instead	O
of	O
being	O
routed	O
elsewhere	O
,	O
put	O
on	O
the	O
metaphorical	O
"	O
slow	O
path	O
"	O
,	O
in	O
this	O
example	O
usually	O
implemented	O
by	O
software	O
running	O
on	O
the	O
control	O
processor	O
.	O
</s>
<s>
Specific	O
implementations	O
of	O
networking	B-Architecture
software	I-Architecture
architectures	O
have	O
been	O
developed	O
that	O
leverage	O
the	O
concept	O
of	O
a	O
fast	B-General_Concept
path	I-General_Concept
to	O
maximize	O
the	O
performance	O
of	O
packet	O
processing	O
software	O
.	O
</s>
<s>
In	O
these	O
implementations	O
,	O
the	O
networking	O
stack	O
is	O
split	O
into	O
two	O
layers	O
and	O
the	O
lower	O
layer	O
,	O
typically	O
called	O
the	O
fast	B-General_Concept
path	I-General_Concept
,	O
processes	O
the	O
majority	O
of	O
incoming	O
packets	O
outside	O
the	O
OS	O
environment	O
without	O
incurring	O
any	O
of	O
the	O
OS	O
overheads	O
that	O
degrade	O
overall	O
performance	O
.	O
</s>
<s>
Some	O
hardware	O
RAID	B-Architecture
controllers	O
implement	O
a	O
"	O
fast	B-General_Concept
path	I-General_Concept
"	O
for	O
write-through	O
access	O
which	O
bypasses	O
the	O
controller	O
's	O
cache	O
in	O
certain	O
situations	O
.	O
</s>
<s>
This	O
tends	O
to	O
increase	O
IOPS	O
,	O
particularly	O
for	O
solid-state	B-Device
drives	I-Device
.	O
</s>
