<s>
Raymond	B-Operating_System
's	I-Operating_System
Algorithm	I-Operating_System
is	O
a	O
lock	O
based	O
algorithm	O
for	O
mutual	B-Operating_System
exclusion	I-Operating_System
on	O
a	O
distributed	B-Architecture
system	I-Architecture
.	O
</s>
<s>
It	O
imposes	O
a	O
logical	O
structure	O
(	O
a	O
K-ary	B-Data_Structure
tree	I-Data_Structure
)	O
on	O
distributed	O
resources	O
.	O
</s>
<s>
Each	O
node	O
maintains	O
a	O
FIFO	B-Operating_System
queue	O
of	O
requests	O
each	O
time	O
that	O
it	O
sees	O
the	O
token	O
;	O
</s>
<s>
If	O
a	O
node	O
i	O
(	O
not	O
holding	O
the	O
token	O
)	O
wishes	O
to	O
receive	O
the	O
token	O
in	O
order	O
to	O
enter	O
into	O
its	O
critical	B-Operating_System
section	I-Operating_System
,	O
it	O
sends	O
a	O
request	O
to	O
its	O
parent	O
,	O
node	O
j	O
.	O
</s>
<s>
Node	O
j	O
will	O
utilize	O
the	O
token	O
to	O
enter	O
into	O
its	O
critical	B-Operating_System
section	I-Operating_System
if	O
it	O
is	O
at	O
the	O
head	O
of	O
the	O
queue	O
when	O
the	O
token	O
is	O
received	O
.	O
</s>
<s>
Raymond	B-Operating_System
's	I-Operating_System
algorithm	I-Operating_System
is	O
guaranteed	O
to	O
be	O
O(log n )	O
per	O
critical	B-Operating_System
section	I-Operating_System
entry	O
if	O
the	O
processors	O
are	O
organized	O
into	O
a	O
K-ary	B-Data_Structure
tree	I-Data_Structure
.	O
</s>
