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From YouTube: Ceph Crimson/Seastore Meeting 2023-03-15
Description
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A
A
Okay,
so
first
some
cabinets
trivia,
so.
C
D
A
D
Yeah
I
I'm
have
reviewed
and
emerged
the
code
here,
PR
and
yeah
I
think
the
design
of
the
read
optimized
device
tiering
should
be
aligned
now
and
I'm.
Also
reviewing
the
multi-core.
D
A
B
This
week,
I
was
still
mostly
verifying
the
LBA
400
PRS
in
scene
suggested
and
and
I.
We
also
try
to
design
the
machinery
for
cloning
in
systore,
but
I
think
that's
that's
a
large
part.
We
are
missing
for
the
design,
and
that
is
snap
trimming
and
snapshot
recovery.
A
Yeah,
so
the
most
common
you're
correct
and
not
the
most
common
right
pattern
is
that
you
clone
head
to
a
snap,
ID
larger
than
any
previous
snap,
ID
and
then
right
to
head.
That
is
indeed
the
most
common
pattern.
Most
of
the
time,
however,
recovery
doesn't
work
that
way
during
recovery.
A
Well,
in
whatever
order
they
happen
to
come
up,
but
the
OSD
maintains
metadata
in
the
Clone,
subsets,
I,
think
struct
or
a
map
in
the
snaps
up
and
when
it
submits
the
iOS
to
actually
write
out
each
clone,
it
will
do
a
clone
range
to
clone
the
portions
of
the
object
that
it
shares
with
its
neighbors,
though,
unfortunately,
you
have
to
tolerate
that
there
either.
You
have
to
tolerate
that
which
I
think
you
actually
do,
because
we
have
good
reasons
for
it.
A
It
reduces
latency
during
recovery
or
you'd
have
to
change
the
way
the
OSD
does.
Recovery.
A
A
A
B
Yes,
actually
I
I
haven't
I,
haven't
given
this,
given
the
recovery
and
the
snap
trimming
very
careful
thoughts,
but
it
appears
to
me
that
if
we
can
run
out
in
our
design,
we
only
record
the
the
most
recent
clone
objects:
snap
ID
and
object
data
or
object
data
in
the
header
object,
but
I
think
we
can
no
matter
no
matter
how
head
object
or
a
clone
object.
B
Yeah,
and
that
seems
to
be
able
to
result
the
the
issue
around
snap
trimming
and
recovery,
but.
A
Maybe
but
I
don't
think
so.
I
think
the
end
result
will
be
that
it'll
be
really
complicated
and
you'll
be
mixing
the
ref
counting
portion
from
just
being
something
that
object.
Data
Handler
and
the
letter
layers
need
to
worry
about
something
that
the
O
nodes
need
to
worry
about
too
I
think
the
end
result
will
be
much
more
complicated.
A
D
A
Yeah
that
actually
does
make
make
sense.
So
my
suggestion
is
that
each
one
of
these
ranges
will
be
owned
by
some
a
ladder
range
and
then,
when
it
gets
cloned
to
another
object
that
object's
object.
Data
Handler,
instead
of
referring
to
those
logical
addresses
directly
or
those
physical
addresses
directly,
will
have
an
interaction
back
to
the
old
one,
in
other
words,
you're
still
going
to
build
something
a
bit
like
a
linked
list,
but
you'll
do
it
in
the
object
data
Handler
instead
of
in
the
onode
and
it'll
need
to
be.
A
You
can't
make
strong
assumptions
about
clone
ordering
because,
like
I
said,
the
Clones
may
not
all
even
exist
at
the
same
time,
because
recovery
might
happen
in
any
order,
but
you
can
probably
create
some
kind
of
extent
that
acts
like
the
blob
Concept
in
Blue
Store,
where,
when
you
have
a
when
you
have
multiple
objects,
referring
to
the
same
extents,
instead
of
referring
to
those.
C
A
Directly,
they
instead
refer
to
this
interaction
and
that
in
direction
is
what
owns
them.
So
the
back
ref
would
point
at
that
interaction
instead
of
at
the
original
said
about
the
original
object,
object
data,
Handler
regions.
B
Okay,
I'll
try
to
give
it
more
more
careful
thoughts.
A
So,
in
other
words
like
when,
when
you
clone
an
object,
you
would
take
all
of
its
regions
and
the
new
clone
would
refer
back
to
that
that
a
letter
via
US
like
a
secondary
extent
or.
D
A
Special
a
letter,
a
special,
a
ladder,
entry
that
references,
the
old
one,
was
that
something
like
what
you
had
in
my
nation.
C
D
A
B
Because
not
not
quite
I
was
mostly
trying
to
trying
to
understand
how
a
classic
osd's
PG
layer
handle
the
Clone
clone
operation.
I
didn't
pay
much
attention
to
the
store.
I
think
that
I
should
go
into
blue
store
later
I
mean
I
mean,
then
the
next
step
should
be
Look
Into,
the
Blue
Store.
A
A
B
Think
yeah,
I
I
don't
quite
understand
the
L
address
in
Direction
right
now,
but
I
can
I
think
I
can
discuss,
discuss
with
Ying
Shin
later
yeah
yeah,
because
I
think
maybe
maybe
it'll
be
more
effective.
If
we
communicate
in
Mandarin
I'm
sorry
about
that
quite.
C
B
Thanks
really
really
sorry,
oh
yeah.