Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 7B2ED87A for ; Sun, 23 Aug 2015 01:23:45 +0000 (UTC) X-Greylist: whitelisted by SQLgrey-1.7.6 Received: from mail-ig0-f175.google.com (mail-ig0-f175.google.com [209.85.213.175]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 304C8E8 for ; Sun, 23 Aug 2015 01:23:44 +0000 (UTC) Received: by igfj19 with SMTP id j19so36123939igf.1 for ; Sat, 22 Aug 2015 18:23:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-type; bh=YRhIKPoVoSWqfzJT0yQyTEZndUne8zc9gzGO/OtMP5o=; b=KWeLDWwU2fSLChoe2DWU7qHa36vfygg7nue/5K62GwkDtlmV3g4cwdjOzQmFljrax8 WYIddNPKwqfT+rYHBfu6iw7/oTrsGyLSQNIiYq7saKh8dqXMSz+3c+injJYlkdS25IVV WEX85hbN2ctquzlOizzTmT4dRuE5aVO8v02fQmTP46dKXNpGrLXJCzF8lYsZALcaOkrg XfQjGcT0DZszzxqv+z9Az6oo0NuC5Vm8P8GFujDXLWLv676tsWvOfXC4EUDubFKn0/Vb bHR1XyKLaYWCUtGIcvlxqE8iBtA/TEEdRnU3cXn7IGERX57UlJ9qGUQyisOAymyXExjz IzMA== X-Received: by 10.50.62.46 with SMTP id v14mr9645116igr.79.1440293023593; Sat, 22 Aug 2015 18:23:43 -0700 (PDT) MIME-Version: 1.0 References: <55B723EA.7010700@voskuil.org> <55B939CF.1080903@voskuil.org> <3390F712-879A-46E9-ABCD-D35B51190304@bitsofproof.com> In-Reply-To: From: Eric Lombrozo Date: Sun, 23 Aug 2015 01:23:33 +0000 Message-ID: To: Tamas Blummer , =?UTF-8?B?Sm9yZ2UgVGltw7Nu?= , Matt Corallo Content-Type: multipart/alternative; boundary=047d7bd771220b3d48051df05aeb X-Spam-Status: No, score=-1.0 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, FREEMAIL_FROM, HTML_MESSAGE, RCVD_IN_DNSWL_LOW, URIBL_BLACK autolearn=no version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.linux-foundation.org Cc: Bitcoin Dev , Libbitcoin Subject: Re: [bitcoin-dev] Libconsensus separated repository (was Bitcoin Core and hard forks) X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Bitcoin Development Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 23 Aug 2015 01:23:45 -0000 --047d7bd771220b3d48051df05aeb Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable I've been pushing for greater modularization since I first got into bitcoin. I got quickly frustrated when I was only able to get through very few things (i.e. moving core structure serialization classes to a separate unit not called main). Working on Bitcoin has an added layer of frustration that goes beyond most open source projects: even though we're clearly in userland working at the application layer, a good layered protocol design is still lacking. We have no standards process separate from what basically amount to updates to one specific reference implementation. And we all need to agree on any major change, since a blockchain that is easily forked in contentious ways pretty much defeats its own purpose. I went off to develop my own stack, where I could more easily avoid politics and focus on engineering. But I now understand the politics are inevitable. Bitcoin is inherently a cooperative project. Several people have poured themselves passionately into the reference codebase, most of whom did it (at least initially) purely as unpaid volunteers. There's a lot of love that's gone into this. But it's become pretty clear that the modularization is no longer merely a matter of good engineering - it is essential to resolving serious political challenges. Perhaps the most frustrating thing of all is watching people pushing for relatively superficial yet highly controversial changes while we still lack the proper infrastructure to handle these kinds of divergences of opinion without either stagnating or becoming polarized. I could continue working to reimplement an entire stack from scratch, as several others have also done - but besides the serious effort duplication this entails, it doesn't really seem like it will ultimately be a convergent process. It's too easy to let ego and habit dictate one's preferences rather than rational engineering considerations. I know that some might feel I'm just preaching to the choir, but we should probably take a step back from implementation hackery and try to specify some core protocol layers, focusing on interfaces. Specifically, we need a consensus layer that doesn't try to specify networking, storage, wallets, UI, etc. Let different people improve upon these things independently in their own implementations. What matters is that we all converge on a common history and state. At the same time, let's open up more competition on all these other things that are separate from the consensus layer. If only we were to dedicate a fraction of the effort we've put into this whole block size circus into what's actually important...and I blame myself as well... On Sat, Aug 22, 2015, 4:05 AM Tamas Blummer via bitcoin-dev < bitcoin-dev@lists.linuxfoundation.org> wrote: > On Aug 21, 2015, at 21:46, Jorge Tim=C3=B3n wrote: > > On Thu, Aug 20, 2015 at 10:35 AM, Tamas Blummer > wrote: > > Every re-implementation, re-factoring even copy-paste introduces a risk o= f > disagreement, > but also open the chance of doing the work better, in the sense of > software engineering. > > > But you don't want something better, you want something functionally > identical. > You may want to watch sipa's explanation on why "the implementation is > the specification" and the reasons to separate libconsensus: > https://youtu.be/l3O4nh79CUU?t=3D764 > > > I do want something better, but not for the focus you have. > > Not because what you produce was not high quality, but because quality is > achieved at a very > high cost and is hard to uphold over generations of developer. You focus > on a single use case > while there are many out there for distributed ledgers. > > I think in an infrastructure for enterprise applications, building > consensus on the ledger is a > cornerstone there, but is only a piece of the solution. I built several > commercially successful > deployments where I delegated the consensus building to a border router, = a > Bitcoin Core, > then interfaced that trusted peer with my implementation that accepted > Core=E2=80=99s decisions > in an SPV manner. One might think of this setup as wasteful and unsuitabl= e > for =E2=80=9Csmall devices=E2=80=9D > therefore an example of centralization people here try to avoid. > > Enterprises have sufficient resources. Solving the business problem is > valuable to them even at > magnitudes higher cost than a hobbyist would bear. > > For mainstream adoption you need to get enterprises on board too, and > that is what I care of. > Enterprises want code that is not only high quality, but is easy to > maintain with a development > team with high attrition. One has to take whatever help is offered for > that, and one is modern > languages and runtimes. > > Bits of Proof=E2=80=99s own implementation of the scripts was not practic= ally > relevant in my commercially > successful deployments, because of the use of a border router, but it > helped development, > enabling easier debug and precise error feedback esp. end even after Core > had a reject message. > > I integrated libconsensus only for the hope that is significantly fastens > application side tx verification, > which it has turned out it does not, until secp265k1 is integrated. > > I would likely use an other extended libconsensus too, but do not think > there was a dependency on > that for enterprise development. > > It would help there more to have a slim protocol server, no wallet, no > rpc, no qt but a high > performance remoting API. > > Since you already depend on libconsensus for VerifyScript, wouldn't it > be nice that it also offered VerifyTx, VerifyHeader and VerifyBlock? > You would still have complete control over storage, concurrency, > networking, policy... > My plan is for the C API to interface with the external storage by > passing a function pointer to it. > > > Storage and validation is non-trivially interconnected, but I now the > separation can be done, > since I did it. > > Excuse me, but function pointers is a pattern I used in the 80=E2=80=99s.= I know > that they are behind > the curtain of modern abstractions with similar use, I still prefer not t= o > see them again. > > Tamas Blummer > > _______________________________________________ > bitcoin-dev mailing list > bitcoin-dev@lists.linuxfoundation.org > https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev > --047d7bd771220b3d48051df05aeb Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable

I've been pushing for greater modularization since I fir= st got into bitcoin. I got quickly frustrated when I was only able to get t= hrough very few things (i.e. moving core structure serialization classes to= a separate unit not called main). Working on Bitcoin has an added layer of= frustration that goes beyond most open source projects: even though we'= ;re clearly in userland working at the application layer, a good layered pr= otocol design is still lacking. We have no standards process separate from = what basically amount to updates to one specific reference implementation. = And we all need to agree on any major change, since a blockchain that is ea= sily forked in contentious ways pretty much defeats its own purpose.

I went off to develop my own stack, where I could more easil= y avoid politics and focus on engineering. But I now understand the politic= s are inevitable. Bitcoin is inherently a cooperative project. Several peop= le have poured themselves passionately into the reference codebase, most of= whom did it (at least initially) purely as unpaid volunteers. There's = a lot of love that's gone into this. But it's become pretty clear t= hat the modularization is no longer merely a matter of good engineering - i= t is essential to resolving serious political challenges.

Perhaps the most frustrating thing of all is watching people= pushing for relatively superficial yet highly controversial changes while = we still lack the proper infrastructure to handle these kinds of divergence= s of opinion without either stagnating or becoming polarized.

I could continue working to reimplement an entire stack from= scratch, as several others have also done - but besides the serious effort= duplication this entails, it doesn't really seem like it will ultimate= ly be a convergent process. It's too easy to let ego and habit dictate = one's preferences rather than rational engineering considerations.

I know that some might feel I'm just preaching to the ch= oir, but we should probably take a step back from implementation hackery an= d try to specify some core protocol layers, focusing on interfaces. Specifi= cally, we need a consensus layer that doesn't try to specify networking= , storage, wallets, UI, etc. Let different people improve upon these things= independently in their own implementations. What matters is that we all co= nverge on a common history and state. At the same time, let's open up m= ore competition on all these other things that are separate from the consen= sus layer.

If only we were to dedicate a fraction of the effort we'= ve put into this whole block size circus into what's actually important= ...and I blame myself as well...


On Sat, Aug 22, 2015, 4:05 = AM=C2=A0Tamas Blummer via bitcoin-dev <bitcoin-dev@lists.linuxfoundation.org> wrote= :
On Aug 21, 2015, at 21:46, Jorge Tim= =C3=B3n <jtimon@jt= imon.cc> wrote:

On Thu, Aug 20, 2015 at 10:35 AM, Tamas Blummer <tamas@bits= ofproof.com> wrot= e:
Every re-implement= ation, re-factoring even copy-paste introduces a risk of disagreement,
b= ut also open the chance of doing the work better, in the sense of software = engineering.

But you don't want something better, you want somethi= ng functionally identical.
You may want to watch sipa's explanation on why &= quot;the implementation is
the specification" and the reasons to separate l= ibconsensus:
https://youtu.be/l3O4nh79CUU?t=3D764

I do want something better, but not for the focus you = have.=C2=A0

Not because what you produce was not h= igh quality, but because quality is achieved at a very
high cost = and is hard to uphold over generations of developer. You focus on a single = use case
while there are many out there for distributed ledgers.<= /div>

I think in an infrastructure for enterprise applic= ations, building consensus on the ledger is a=C2=A0
cornerstone t= here, but is only a piece of the solution. I built several commercially suc= cessful
deployments where I delegated the consensus building to a= border router, a Bitcoin Core,=C2=A0
then interfaced that truste= d peer with my =C2=A0implementation that accepted Core=E2=80=99s decisions= =C2=A0
in an SPV manner. One might think of this setup as wastefu= l and unsuitable for =E2=80=9Csmall devices=E2=80=9D
therefore an= example of centralization people here try to avoid.

Enterprises have sufficient resources. Solving the business problem is v= aluable to them even at=C2=A0
magnitudes higher cost than a hobby= ist would bear.

For mainstream adoption you need t= o get enterprises on board too, and =C2=A0that is what I care of.=C2=A0
Enterprises want code that is not only high quality, but is easy to = maintain with a development=C2=A0
team with high attrition. One h= as to take whatever help is offered for that, and one is modern=C2=A0
=
languages and runtimes.

Bits of Proof=E2= =80=99s own implementation of the scripts was not practically relevant in m= y commercially
successful deployments, because of the use of a bo= rder router, but it helped development,=C2=A0
enabling easier deb= ug and precise error feedback esp. end even after Core had a reject message= .=C2=A0

I integrated libconsensus only for t= he hope that is significantly fastens application side tx verification,
=C2=A0which it has turned out it does not, until secp265k1 is integr= ated.

I would likely use an other extended libcons= ensus too, but do not think there was a dependency on=C2=A0
that = for enterprise development.=C2=A0

It would help th= ere more to have a slim protocol server, no wallet, no rpc, no qt but a hig= h=C2=A0
performance remoting API.

Since you already depend o= n libconsensus for VerifyScript, wouldn't it
be nice that it also offered Ve= rifyTx, VerifyHeader and VerifyBlock?
You would still have complete control over= storage, concurrency,
networking, policy...
My plan is for the C API to interface wi= th the external storage by
passing a function pointer to it.

<= /div>
Storage and validation is non-trivially interconnected, but I now= the separation can be done,
since I did it.=C2=A0

=
Excuse me, but function pointers is a pattern I used in the 80= =E2=80=99s. I know that they are behind=C2=A0
the curtain of mode= rn abstractions with similar use, I still prefer not to see them again.

T= amas Blummer

_______________________________________________ bitcoin-dev mailing list
= bitcoin-dev@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mail= man/listinfo/bitcoin-dev
--047d7bd771220b3d48051df05aeb--