<s>
This	O
is	O
a	O
list	B-Language
of	I-Language
PHP	I-Language
accelerators	I-Language
.	O
</s>
<s>
Alternative	O
PHP	O
Cache	O
is	O
a	O
free	B-Application
and	O
open	B-License
(	O
PHP	B-Language
license	I-Language
)	O
framework	O
that	O
caches	O
the	O
output	O
of	O
the	O
PHP	O
bytecode	O
compiler	O
in	O
shared	B-Operating_System
memory	I-Operating_System
,	O
thus	O
reducing	O
parsing	O
and	O
disk	O
I/O	O
overhead	O
for	O
later	O
requests	O
;	O
and	O
a	O
shared	B-Operating_System
memory	I-Operating_System
cache	O
for	O
user	O
data	O
.	O
</s>
<s>
For	O
an	O
application	O
consisting	O
of	O
a	O
large	O
source	O
code	O
base	O
such	O
as	O
Drupal	B-Application
,	O
a	O
3x	O
increase	O
in	O
page	O
generation	O
speed	O
is	O
possible	O
as	O
a	O
result	O
.	O
</s>
<s>
Since	O
March	O
2013	O
,	O
a	O
beta	O
version	O
of	O
APCu	O
(	O
APC	O
User	O
Cache	O
)	O
is	O
available	O
,	O
in	O
which	O
all	O
opcode	O
caching	O
abilities	O
have	O
been	O
removed	O
to	O
support	O
user	O
caches	O
in	O
shared	B-Operating_System
memory	I-Operating_System
using	O
the	O
familiar	O
APC	O
API	O
.	O
</s>
<s>
eAccelerator	B-Language
was	O
born	O
in	O
December	O
2004	O
as	O
a	O
fork	O
of	O
the	O
Turck	B-Protocol
MMCache	I-Protocol
project	O
.	O
</s>
<s>
Turck	B-Protocol
MMCache	I-Protocol
was	O
created	O
by	O
Dmitry	O
Stogov	O
and	O
much	O
of	O
the	O
eAccelerator	B-Language
code	O
is	O
still	O
based	O
on	O
his	O
work	O
.	O
</s>
<s>
eAccelerator	B-Language
also	O
contained	O
a	O
PHP	O
encoder	O
and	O
loader	O
,	O
but	O
the	O
development	O
staff	O
discontinued	O
the	O
encoder	O
and	O
removed	O
this	O
feature	O
after	O
December	O
2006	O
.	O
</s>
<s>
eAccelerator	B-Language
will	O
not	O
work	O
with	O
any	O
other	O
versions	O
of	O
PHP	O
.	O
</s>
<s>
eAccelerator	B-Language
can	O
only	O
be	O
used	O
with	O
the	O
thread-safe	O
version	O
of	O
PHP	O
.	O
</s>
<s>
The	O
last	O
public	O
activity	O
was	O
the	O
transfer	O
to	O
GitHub	B-Application
by	O
Hans	O
Rakers	O
.	O
</s>
<s>
Launched	O
in	O
2001	O
,	O
ionCube	O
PHP	B-Language
Accelerator	I-Language
(	O
PHPA	O
)	O
was	O
the	O
first	O
freely	O
available	O
PHP	B-Language
accelerator	I-Language
to	O
compete	O
with	O
the	O
commercial	O
Zend	O
Cache	O
product	O
.	O
</s>
<s>
Although	O
the	O
author	O
of	O
PHPA	O
chose	O
to	O
keep	O
the	O
project	O
closed	O
source	O
in	O
response	O
to	O
early	O
concerns	O
raised	O
by	O
Zeev	O
Suraski	O
of	O
Zend	O
Technologies	O
about	O
the	O
effect	O
that	O
an	O
open	B-License
source	I-License
rival	O
might	O
have	O
on	O
their	O
commercial	O
alternative	O
,	O
the	O
availability	O
of	O
PHPA	O
on	O
a	O
wide	O
variety	O
of	O
platforms	O
led	O
to	O
its	O
extensive	O
adoption	O
worldwide	O
from	O
small	O
sites	O
to	O
Yahoo	O
!	O
.	O
</s>
<s>
It	O
also	O
inspired	O
the	O
redevelopment	O
of	O
APC	O
to	O
use	O
the	O
shared	B-Operating_System
memory	I-Operating_System
execution	O
techniques	O
that	O
PHPA	O
and	O
Zend	O
Cache	O
had	O
adopted	O
instead	O
of	O
deserialization	O
on	O
each	O
request	O
that	O
incurred	O
performance	O
penalties	O
.	O
</s>
<s>
Turck	B-Protocol
MMCache	I-Protocol
is	O
now	O
discontinued	O
.	O
</s>
<s>
eAccelerator	B-Language
is	O
a	O
fork	O
of	O
Turck	B-Protocol
MMCache	I-Protocol
.	O
</s>
<s>
This	O
relatively	O
new	O
opcode	O
caching	O
software	O
has	O
been	O
developed	O
by	O
mOo	O
,	O
one	O
of	O
the	O
developers	O
of	O
Lighttpd	B-Protocol
,	O
to	O
overcome	O
some	O
of	O
the	O
limitations	O
of	O
the	O
existing	O
solutions	O
at	O
that	O
time	O
;	O
such	O
as	O
being	O
able	O
to	O
use	O
it	O
with	O
new	O
PHP	O
versions	O
as	O
they	O
arrive	O
.	O
</s>
<s>
PhpExpress	O
is	O
a	O
free	B-Application
PHP	O
opcode	O
cache	O
that	O
loads	O
both	O
Nu-Coder	O
(	O
commercial	O
)	O
encoded	O
and	O
plain	O
PHP	O
files	O
directly	O
into	O
the	O
PHP	O
engine	O
,	O
saving	O
loading	O
time	O
and	O
boosting	O
performance	O
of	O
PHP	O
applications	O
.	O
</s>
<s>
Zend	O
Opcache	O
is	O
an	O
open	B-License
source	I-License
component	O
of	O
Zend	B-Protocol
Server	I-Protocol
and	O
Zend	B-Protocol
Server	I-Protocol
Community	O
Edition	O
.	O
</s>
<s>
It	O
stores	O
precompiled	O
script	O
bytecode	O
in	O
shared	B-Operating_System
memory	I-Operating_System
.	O
</s>
<s>
Zend	O
provides	O
another	O
component	O
,	O
Zend	O
Guard	O
Loader	O
,	O
in	O
order	O
to	O
load	O
encoded	O
applications	O
with	O
Zend	B-Protocol
Server	I-Protocol
and	O
Zend	B-Protocol
Server	I-Protocol
Community	O
Edition	O
.	O
</s>
<s>
It	O
has	O
a	O
complete	O
set	O
of	O
performance	O
capabilities	O
that	O
includes	O
more	O
than	O
a	O
simple	O
PHP	B-Language
accelerator	I-Language
.	O
</s>
<s>
Zend	O
Platform	O
and	O
Zend	O
Core	O
are	O
now	O
in	O
'	O
end	O
of	O
life	O
 '	O
status	O
and	O
are	O
replaced	O
with	O
Zend	B-Protocol
Server	I-Protocol
.	O
</s>
<s>
A	O
free	B-Application
,	O
open	B-License
source	I-License
(	O
New	O
BSD	B-Operating_System
License	I-Operating_System
)	O
,	O
PHP	B-Language
accelerator	I-Language
developed	O
by	O
Microsoft	O
for	O
PHP	O
under	O
Windows	O
.	O
</s>
<s>
The	O
extension	O
is	O
primarily	O
used	O
with	O
Internet	B-Application
Information	I-Application
Services	I-Application
and	O
non-thread-safe	O
build	O
of	O
PHP	O
via	O
FastCGI	O
protocol	O
.	O
</s>
<s>
Name	O
Availability	O
Opcode	O
cache	O
File	O
cache	O
Resolve	O
file	O
path	O
cache	O
Object/session	O
cache	O
Optimization	O
Cache	O
in	O
memory	O
Source	O
encoding	O
APC	O
Discontinued	O
eAccelerator	B-Language
Discontinued	O
PHP	B-Language
Accelerator	I-Language
(	O
PHPA	O
)	O
Discontinued	O
Turck	B-Protocol
MMCache	I-Protocol
Discontinued	O
XCache	O
Discontinued	O
Nusphere	O
PhpExpress	O
Discontinued	O
Zend	O
Opcache	O
(	O
ex	O
.	O
</s>
<s>
PHP	B-Language
accelerators	I-Language
Availability	O
OS	O
Web	O
servers	O
PHP	O
version	O
Windows	O
Linux	O
FreeBSD	O
macOS	O
NetBSD	O
Solaris	O
IIS	O
Apache	O
Nginx	O
5.2	O
5.3	O
5.4	O
5.5	O
5.6	O
7.0	O
7.1	O
7.2	O
7.3	O
APC	O
Discontinued	O
eAccelerator	B-Language
Discontinued	O
ionCube	O
Discontinued	O
Turck	B-Protocol
MMCache	I-Protocol
Discontinued	O
XCache	O
Discontinued	O
Nusphere	O
PhpExpress	O
Discontinued	O
Zend	O
Opcache	O
(	O
ex	O
.	O
</s>
<s>
Zend	O
Guard	O
Loader	O
,	O
formerly	O
known	O
as	O
Zend	O
Optimizer	O
,	O
is	O
a	O
free	B-Application
PHP	O
extension	O
by	O
Zend	O
Technologies	O
that	O
loads	O
files	O
encoded	O
and	O
obfuscated	O
by	O
Zend	O
Guard	O
.	O
</s>
