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From Stack <st...@duboce.net>
Subject Re: DISCUSS: Protobufs?
Date Tue, 02 Feb 2016 21:14:58 GMT
On Tue, Feb 2, 2016 at 12:16 PM, Enis Söztutar <enis.soz@gmail.com> wrote:

> bq. java is second class in flatbuffers).
> This is an Android project, no? I thought Java is the primary target.
>
>  I was looking at this Enis:
https://google.github.io/flatbuffers/flatbuffers_support.html
St.Ack



> On Tue, Feb 2, 2016 at 12:14 PM, Stack <stack@duboce.net> wrote:
>
> > On Tue, Feb 2, 2016 at 11:47 AM, Enis Söztutar <enis.soz@gmail.com>
> wrote:
> >
> > > BTW, we should also be looking at
> https://google.github.io/flatbuffers/
> > or
> > > https://capnproto.org/ for serialization as an option. The idea is to
> > not
> > > allocate objects and prevent allocations altogether.
> > >
> > >
> > Agree (watching capnproto w/ a while, the java implementation has
> stalled.
> > java is second class in flatbuffers).
> > St.Ack
> >
> >
> >
> > > We are allocating PB objects for every Get / Put, then we allocate our
> > Get
> > > / Put objects. At least we can save on 1.
> > >
> > > Although, just switching our serialization format again will be a huge
> > > undertaking with obvious wire-incompatibility issues. If PB3 or 2.x
> gives
> > > us what we want in terms of preventing big byte[] allocations, we would
> > > gain regardless.
> > >
> > > Enis
> > >
> > > On Tue, Feb 2, 2016 at 11:41 AM, Enis Söztutar <enis.soz@gmail.com>
> > wrote:
> > >
> > > > Google guys over at
> > > > https://github.com/grpc/grpc-java/issues/1054#issuecomment-147295224
> > are
> > > > saying that CIS changes may be coming to 2.x from what I understand.
> If
> > > so,
> > > > our life would be easier. Even so, I'm 100% sure we have to do
> shading
> > > > since Hadoop will not change it's PB dependency anytime soon.
> > > >
> > > > We have to do this before doing shading:
> > > > https://issues.apache.org/jira/browse/HBASE-15174
> > > >
> > > > Enis
> > > >
> > > > On Tue, Feb 2, 2016 at 8:15 AM, Stack <stack@duboce.net> wrote:
> > > >
> > > >> Thanks Duo. If proto3 had what we wanted, you are suggesting we
> might
> > > move
> > > >> to proto3 setting it to do proto2 support and shade it so we don't
> > clash
> > > >> with other includes of pb?
> > > >>
> > > >> Regards Anoop comment, the note on the end of this issue looks
> > promising
> > > >> but I don't know when it'd see the light of day:
> > > >>
> https://github.com/grpc/grpc-java/issues/1054#issuecomment-147295224
> > > >>
> > > >> St.Ack
> > > >>
> > > >>
> > > >> On Mon, Feb 1, 2016 at 10:49 PM, Anoop John <anoop.hbase@gmail.com>
> > > >> wrote:
> > > >>
> > > >> > UnsafeByteStrings - This may help us to avoid copy even with
out
> our
> > > >> > HBaseZeroCopyByteString stuff.  But with a DirectByteBuffer,
it
> has
> > to
> > > >> copy
> > > >> > data to onheap byte[].   We even want a DBB backing !
> > > >> >
> > > >> > -Anoop-
> > > >> >
> > > >> > On Tue, Feb 2, 2016 at 12:07 PM, 张铎 <palomino219@gmail.com>
> wrote:
> > > >> >
> > > >> > > https://groups.google.com/forum/#!topic/protobuf/wAqvtPLBsE8
> > > >> > >
> > > >> > > PB2 and PB3 are wire compatible, and of course, protobuf-java
is
> > not
> > > >> > > compatible so dependency will be a problem... But I think
the
> > shaded
> > > >> > client
> > > >> > > and server can solve the problem?
> > > >> > >
> > > >> > > Thanks.
> > > >> > >
> > > >> > > 2016-02-02 14:27 GMT+08:00 Stack <stack@duboce.net>:
> > > >> > >
> > > >> > > > We are running into a few issues with protobufs.
> > > >> > > >
> > > >> > > > + PB always copies all data before making a Message.
This
> > > generates
> > > >> > > garbage
> > > >> > > > unnecessarily.
> > > >> > > > + CodedInputStream does not support ByteBuffers in
2.5. In 2.6
> > it
> > > >> does
> > > >> > > but
> > > >> > > > again, copies the data out of the BB always; this is
> especially
> > > >> painful
> > > >> > > > when the BB is a DBB with its data offheap and intent
is to
> keep
> > > >> data
> > > >> > > > offheap.
> > > >> > > >
> > > >> > > > There are other issues. CIS allocates 4k buffers regardless
> (See
> > > >> > > > HBASE-15177).
> > > >> > > > And then there was the HBaseZeroCopyByteString fun
and games
> we
> > > had
> > > >> a
> > > >> > > while
> > > >> > > > back.
> > > >> > > >
> > > >> > > > 3.0 PB adds UnsafeByteStrings so can do zero copy.
Thats good.
> > But
> > > >> PB3
> > > >> > is
> > > >> > > > incompatible with PB2 (or at least, it looks like PB2
clients
> > > can't
> > > >> > talk
> > > >> > > to
> > > >> > > > PB3 [1]).
> > > >> > > >
> > > >> > > > There is javanano protobufs. All is open access, but
it too
> > looks
> > > >> > > different
> > > >> > > > to PB2 (i've not tried it).
> > > >> > > >
> > > >> > > > Protostuff seems really quiet these times [2].
> > > >> > > >
> > > >> > > > Fork (and shade)?
> > > >> > > >
> > > >> > > > Thoughts?
> > > >> > > >
> > > >> > > > St.Ack
> > > >> > > >
> > > >> > > > 1. https://github.com/google/protobuf/releases
> > > >> > > > 2. https://groups.google.com/forum/#!forum/protostuff
> > > >> > > >
> > > >> > >
> > > >> >
> > > >>
> > > >
> > > >
> > >
> >
>

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