<s>
Yaws	B-Application
(	O
Yet	B-Application
another	I-Application
web	I-Application
server	I-Application
)	O
is	O
a	O
web	B-Application
server	I-Application
written	O
in	O
Erlang	B-Operating_System
by	O
Claes	O
(	O
klacke	O
)	O
Wikström	O
.	O
</s>
<s>
Yaws	B-Application
can	O
be	O
embedded	O
into	O
other	O
Erlang-based	O
applications	O
or	O
run	O
as	O
a	O
regular	O
standalone	O
web	B-Application
server	I-Application
.	O
</s>
<s>
Because	O
Yaws	B-Application
uses	O
Erlang	B-Operating_System
's	O
lightweight	O
threading	O
system	O
,	O
it	O
performs	O
well	O
under	O
high	O
concurrency	O
.	O
</s>
<s>
A	O
load	O
test	O
conducted	O
in	O
2002	O
comparing	O
Yaws	B-Application
and	O
Apache	B-Application
found	O
that	O
with	O
the	O
hardware	O
tested	O
,	O
Apache	B-Application
2.0.39	O
with	O
the	O
worker	O
MPM	O
failed	O
at	O
4,000	O
concurrent	O
connections	O
,	O
while	O
Yaws	B-Application
continued	O
functioning	O
with	O
over	O
80,000	O
concurrent	O
connections	O
.	O
</s>
<s>
The	O
load	O
test	O
concludes	O
,	O
"	O
The	O
problem	O
with	O
Apache	B-Application
is	O
not	O
related	O
to	O
the	O
Apache	B-Application
code	O
per	O
se	O
but	O
is	O
due	O
to	O
the	O
manner	O
in	O
which	O
the	O
underlying	O
operating	O
system	O
(	O
Linux	O
)	O
implements	O
concurrency	O
.	O
</s>
<s>
Erlang	B-Operating_System
does	O
not	O
make	O
use	O
of	O
the	O
underlying	O
OS	O
's	O
threads	O
and	O
processes	O
for	O
managing	O
its	O
own	O
process	O
pool	O
and	O
thus	O
does	O
not	O
suffer	O
from	O
these	O
limitations	O
"	O
.and	O
in	O
the	O
underlined	O
part	O
above	O
(	O
formatting	O
added	O
)	O
,	O
expresses	O
the	O
opinion	O
that	O
the	O
founding	O
technologies	O
make	O
the	O
difference	O
in	O
scalability	O
.	O
</s>
