<s>
Bcachefs	B-Application
is	O
a	O
copy-on-write	B-Language
(	O
COW	O
)	O
file	B-Application
system	I-Application
for	O
Linux-based	O
operating	O
systems	O
.	O
</s>
<s>
Its	O
primary	O
developer	O
,	O
Kent	O
Overstreet	O
,	O
first	O
announced	O
it	O
in	O
2015	O
,	O
and	O
efforts	O
are	O
ongoing	O
to	O
have	O
it	O
included	O
in	O
the	O
mainline	O
Linux	B-Application
kernel	O
.	O
</s>
<s>
It	O
is	O
intended	O
to	O
compete	O
with	O
the	O
modern	O
features	O
of	O
ZFS	B-Application
or	O
Btrfs	B-Operating_System
,	O
and	O
the	O
speed	O
and	O
performance	O
of	O
ext4	B-Application
or	O
XFS	B-Application
.	O
</s>
<s>
Bcachefs	B-Application
is	O
a	O
copy-on-write	B-Language
(	O
COW	O
)	O
file	B-Application
system	I-Application
for	O
Linux-based	O
operating	O
systems	O
.	O
</s>
<s>
Planned	O
or	O
existing	O
features	O
for	O
Bcachefs	B-Application
include	O
caching	B-General_Concept
,	O
full	O
file-system	B-Application
encryption	O
using	O
the	O
ChaCha20	O
and	O
Poly1305	B-Algorithm
algorithms	O
,	O
native	O
compression	B-General_Concept
via	O
zlib	B-Language
,	O
LZ4	B-Language
,	O
and	O
Zstandard	B-Language
,	O
snapshots	B-Application
,	O
CRC-32C	O
and	O
64-bit	O
checksumming	O
.	O
</s>
<s>
It	O
can	O
use	O
multiple	O
block	O
devices	O
,	O
including	O
in	O
RAID	B-Architecture
configurations	O
.	O
</s>
<s>
Bcachefs	B-Application
provides	O
all	O
the	O
functionality	O
of	O
Bcache	B-Application
,	O
a	O
block-layer	O
cache	B-General_Concept
system	O
for	O
Linux	B-Application
,	O
with	O
which	O
Bcachefs	B-Application
shares	O
about	O
80%	O
of	O
its	O
code	O
.	O
</s>
<s>
Primary	O
development	O
has	O
been	O
by	O
Kent	O
Overstreet	O
,	O
the	O
developer	O
of	O
Bcache	B-Application
,	O
which	O
he	O
describes	O
as	O
a	O
"	O
prototype	O
"	O
for	O
the	O
ideas	O
that	O
became	O
Bcachefs	B-Application
.	O
</s>
<s>
Overstreet	O
intends	O
Bcachefs	B-Application
to	O
replace	O
Bcache	B-Application
.	O
</s>
<s>
Overstreet	O
has	O
stated	O
that	O
development	O
of	O
Bcachefs	B-Application
began	O
as	O
Bcache	B-Application
's	O
developers	O
realized	O
that	O
its	O
codebase	O
had	O
"	O
been	O
evolving	O
...	O
into	O
a	O
full	O
blown	O
,	O
general-purpose	O
POSIX	O
filesystem	B-Application
"	O
,	O
and	O
that	O
"	O
there	O
was	O
a	O
really	O
clean	O
and	O
elegant	O
design	O
"	O
within	O
it	O
if	O
they	O
took	O
it	O
in	O
that	O
direction	O
.	O
</s>
<s>
Some	O
time	O
after	O
Bcache	B-Application
was	O
merged	O
in	O
2013	O
into	O
the	O
mainline	O
Linux	B-Application
kernel	O
,	O
Overstreet	O
left	O
his	O
job	O
at	O
Google	B-Application
to	O
work	O
full-time	O
on	O
Bcachefs	B-Application
.	O
</s>
<s>
After	O
a	O
few	O
years	O
 '	O
unfunded	O
development	O
,	O
Overstreet	O
announced	O
Bcachefs	B-Application
in	O
2015	O
,	O
at	O
which	O
point	O
he	O
called	O
the	O
code	O
"	O
more	O
or	O
less	O
feature	O
complete	O
"	O
,	O
and	O
called	O
for	O
testers	O
and	O
contributors	O
.	O
</s>
<s>
He	O
intended	O
it	O
to	O
be	O
an	O
advanced	O
file	B-Application
system	I-Application
with	O
modern	O
features	O
like	O
those	O
of	O
ZFS	B-Application
or	O
Btrfs	B-Operating_System
,	O
with	O
the	O
speed	O
and	O
performance	O
of	O
file	B-Application
systems	I-Application
such	O
as	O
ext4	B-Application
and	O
XFS	B-Application
.	O
</s>
<s>
As	O
of	O
2017	O
Overstreet	O
was	O
receiving	O
financial	O
support	O
for	O
the	O
development	O
of	O
Bcachefs	B-Application
via	O
Patreon	O
.	O
</s>
<s>
Patches	O
had	O
been	O
submitted	O
for	O
review	O
to	O
have	O
Bcachefs	B-Application
included	O
in	O
the	O
mainline	O
Linux	B-Application
kernel	O
,	O
but	O
had	O
not	O
yet	O
been	O
accepted	O
.	O
</s>
<s>
By	O
mid-2019	O
,	O
the	O
desired	O
features	O
of	O
Bcachefs	B-Application
had	O
reached	O
and	O
associated	O
patches	O
to	O
LKML	B-Application
was	O
submitted	O
for	O
peer	O
review	O
.	O
</s>
<s>
As	O
of	O
February	O
2023	O
,	O
Bcachefs	B-Application
has	O
still	O
not	O
been	O
merged	O
into	O
the	O
mainline	O
Linux	B-Application
kernel	O
.	O
</s>
