<s>
AWS	B-Application
Lambda	I-Application
is	O
an	O
event-driven	B-Application
,	O
serverless	B-General_Concept
computing	I-General_Concept
platform	O
provided	O
by	O
Amazon	B-Application
as	O
a	O
part	O
of	O
Amazon	B-Application
Web	I-Application
Services	I-Application
.	O
</s>
<s>
Node.js	B-Language
,	O
Python	B-Language
,	O
Java	B-Language
,	O
Go	B-Application
,	O
Ruby	B-Language
,	O
and	O
C#	B-Application
(	O
through	O
.NET	B-Application
)	O
are	O
all	O
officially	O
supported	O
.	O
</s>
<s>
In	O
late	O
2018	O
,	O
custom	O
runtime	O
support	O
was	O
added	O
to	O
AWS	B-Application
Lambda	I-Application
.	O
</s>
<s>
AWS	B-Application
Lambda	I-Application
supports	O
running	O
native	B-Language
Linux	B-Application
executables	B-Application
by	O
calling	O
them	O
from	O
a	O
supported	O
runtime	O
,	O
such	O
as	O
Node.js	B-Language
.	O
</s>
<s>
For	O
example	O
,	O
Haskell	B-Language
code	O
can	O
be	O
run	O
on	O
Lambda	B-General_Concept
.	O
</s>
<s>
AWS	B-Application
Lambda	I-Application
was	O
primarily	O
designed	O
for	O
image	O
or	O
object	O
uploads	B-Application
to	O
Amazon	B-General_Concept
S3	I-General_Concept
,	O
updates	O
to	O
DynamoDB	B-Application
tables	O
,	O
responding	O
to	O
website	O
clicks	O
,	O
or	O
reacting	O
to	O
sensor	O
readings	O
from	O
an	O
IoT	B-Operating_System
connected	O
device	O
.	O
</s>
<s>
AWS	B-Application
Lambda	I-Application
can	O
also	O
be	O
used	O
to	O
automatically	O
provision	O
back-end	O
services	O
triggered	O
by	O
custom	O
HTTP	O
requests	O
,	O
and	O
"	O
spin	O
down	O
"	O
such	O
services	O
when	O
not	O
in	O
use	O
to	O
save	O
resources	O
.	O
</s>
<s>
These	O
custom	O
HTTP	O
requests	O
are	O
configured	O
in	O
AWS	B-Application
API	O
Gateway	O
,	O
which	O
can	O
also	O
handle	O
authentication	O
and	O
authorization	O
in	O
conjunction	O
with	O
AWS	B-Application
Cognito	O
.	O
</s>
<s>
Unlike	O
Amazon	B-Application
EC2	O
,	O
which	O
is	O
priced	O
by	O
the	O
hour	O
but	O
metered	O
by	O
the	O
second	O
,	O
AWS	B-Application
Lambda	I-Application
is	O
metered	O
by	O
rounding	O
up	O
to	O
the	O
nearest	O
millisecond	O
with	O
no	O
minimum	O
execution	O
time	O
.	O
</s>
<s>
AWS	B-Application
Lambda	I-Application
functions	O
are	O
often	O
used	O
in	O
association	O
with	O
AWS	B-Operating_System
SQS	I-Operating_System
queues	I-Operating_System
to	O
process	O
asynchronous	O
tasks	O
in	O
distributed	O
architectures	O
.	O
</s>
<s>
In	O
2019	O
,	O
at	O
AWS	B-Application
 '	O
annual	O
cloud	O
computing	O
conference	O
(	O
AWS	B-Application
re:Invent	O
)	O
,	O
the	O
AWS	B-Application
Lambda	I-Application
team	O
announced	O
"	O
Provisioned	O
Concurrency	O
"	O
,	O
a	O
feature	O
that	O
"	O
keeps	O
functions	O
initialized	O
and	O
hyper-ready	O
to	O
respond	O
in	O
double-digit	O
milliseconds.	O
"	O
</s>
<s>
The	O
Lambda	B-General_Concept
team	O
described	O
Provisioned	O
Concurrency	O
as	O
"	O
ideal	O
for	O
implementing	O
interactive	O
services	O
,	O
such	O
as	O
web	O
and	O
mobile	O
backends	O
,	O
latency-sensitive	O
microservices	O
,	O
or	O
synchronous	O
APIs.	O
"	O
</s>
<s>
Each	O
AWS	B-Application
Lambda	I-Application
instance	O
is	O
a	O
container	O
created	O
from	O
Amazon	B-Application
Linux	B-Application
AMIs	O
(	O
a	O
Linux	B-Application
distribution	O
related	O
to	O
RHEL	O
)	O
with	O
128	O
–	O
10240	O
MB	O
of	O
RAM	O
(	O
in	O
1	O
MB	O
increments	O
)	O
,	O
512	O
MB	O
to	O
10	O
GB	O
of	O
ephemeral	O
storage	O
in	O
/tmp	O
folder	O
,	O
and	O
a	O
configurable	O
execution	O
time	O
from	O
1	O
to	O
900	O
seconds	O
.	O
</s>
<s>
Since	O
December	O
2020	O
,	O
Lambda	B-General_Concept
has	O
been	O
capable	O
of	O
supporting	O
Docker	O
containers	O
through	O
ECR	O
up	O
to	O
10	O
GB	O
in	O
size	O
.	O
</s>
