<s>
Percona	B-Language
is	O
an	O
American	O
company	O
based	O
in	O
Durham	O
,	O
North	O
Carolina	O
and	O
the	O
developer	O
of	O
a	O
number	O
of	O
open	O
source	O
software	O
projects	O
for	O
MySQL	B-Application
,	O
MariaDB	B-Application
,	O
PostgreSQL	B-Application
,	O
MongoDB	B-Application
and	O
RocksDB	B-Language
users	O
.	O
</s>
<s>
Percona	B-Language
maintains	O
a	O
GitHub	B-Application
repository	O
for	O
their	O
open	O
source	O
software	O
,	O
which	O
can	O
also	O
be	O
downloaded	O
from	O
the	O
Percona	B-Language
website	O
.	O
</s>
<s>
MySQL	B-Application
database	O
software	O
:	O
</s>
<s>
MongoDB	B-Application
database	O
software	O
:	O
</s>
<s>
PostgreSQL	B-Application
database	O
distribution	O
:	O
</s>
<s>
The	O
company	O
’s	O
founders	O
,	O
Peter	O
Zaitsev	O
and	O
Vadim	O
Tkachenko	O
co-authored	O
with	O
Baron	O
Schwartz	O
the	O
book	O
High	O
Performance	O
MySQL	B-Application
(	O
3rd	O
edition	O
)	O
,	O
published	O
by	O
O’Reilly	O
.	O
</s>
