Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id CB3A5ACD for ; Wed, 5 Jul 2017 19:44:29 +0000 (UTC) X-Greylist: whitelisted by SQLgrey-1.7.6 Received: from mail-qk0-f182.google.com (mail-qk0-f182.google.com [209.85.220.182]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id D40CE19B for ; Wed, 5 Jul 2017 19:44:28 +0000 (UTC) Received: by mail-qk0-f182.google.com with SMTP id 16so198846705qkg.2 for ; Wed, 05 Jul 2017 12:44:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=b5pRlPEk4WIa2TeVlexQORXMdqfx6a8VeZuDfnFujS8=; b=L98TazfLYxIi3if7BYz0t/aCNB6woz8PoiLdIiMXA+f6VC6fHMz1rkQQUtB1l3VjkA GUeK3ssUkxz2iicDlyLuX82Dd8ShKxVVh+7mrHisu9KJaahzkvMmXvxXnabZuQJcpBjU csGREYOCKOTq5C+BY4JGa4GO4LdgMQrjcZJIRWdFtdD447BeMfyTkT3TWhHwtGAL1jCF MrCxUm6WprkLWBzKzSvKy5uh3I3ffjL91S0hl2NK9AWuGZWlh/e6nFXrdMd9xT1C+g50 oimNAxxx+cTGBpzfvWkhnlM/oLhnEZqCVZX1km6uSxQAwWV8VyaACJ7JhTOQyhkz7McG aylA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=b5pRlPEk4WIa2TeVlexQORXMdqfx6a8VeZuDfnFujS8=; b=WI+9qtxZQgUPMIW9U9aT3wG2o/sbU8ertfQCufoqlEejTsPqvp+D65IQdCu2RklB7x RJlyDpGmvM1irx10ZemKbPW+yzCaEsOf/xMY5aGdSLmWxt2aDvpdnTaMePrW5bO2nFuW F5L/spMFzp+tAHtkV37lThJ8SllXhdieztNXTa/X44fQhYrbkzmCTCTpiT1otkxtLWOG XClR+UHWzkgC7Zcjbnjg/ggWaU6UF/ABWwH3dah5O/Ielati13fTfDxubmwMXYr2alJN 4PwUEZX5d1sDHT9vssSitBp/NCjm3rdbywwLRRS/SSUx6KuncnSBAqsTPy/obkOLsUIy sWwg== X-Gm-Message-State: AKS2vOzzuSpig31I+hsZlnaNnIbj9YMRG6uvwiZSZOs+lZB30Myf2FUs J7Kdr3kncmChBhvY1VB24153eLzjvg== X-Received: by 10.55.160.196 with SMTP id j187mr52449253qke.145.1499283868043; Wed, 05 Jul 2017 12:44:28 -0700 (PDT) MIME-Version: 1.0 Received: by 10.12.186.175 with HTTP; Wed, 5 Jul 2017 12:44:27 -0700 (PDT) In-Reply-To: <201707050410.45217.luke@dashjr.org> References: <201707050350.53122.luke@dashjr.org> <00qcLaDJFDoC9D6644P_aLf7_n5B1pqCPj_c02QlqySsrJLsB6TZipXMD8L7l3lJcw5NoLP6dphCMruKJCIMkJUIDYbIw0iDd322vsNFmNw=@protonmail.ch> <201707050410.45217.luke@dashjr.org> From: =?UTF-8?Q?Hampus_Sj=C3=B6berg?= Date: Wed, 5 Jul 2017 21:44:27 +0200 Message-ID: To: Luke Dashjr Content-Type: multipart/alternative; boundary="001a114fcfd65f51d60553973ac8" X-Spam-Status: No, score=-1.5 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, FREEMAIL_FROM, HTML_MESSAGE, RCVD_IN_DNSWL_NONE, RCVD_IN_SORBS_SPAM 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@lists.linuxfoundation.org" Subject: Re: [bitcoin-dev] Height based vs block time based thresholds X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Bitcoin Protocol Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 05 Jul 2017 19:44:29 -0000 --001a114fcfd65f51d60553973ac8 Content-Type: text/plain; charset="UTF-8" From the PR change: > Miners must continue setting the bit in LOCKED_IN phase so uptake is visible and acknowledged. Blocks without the applicable bit set are invalid during this period Luke, it seems like the amendments to BIP8 make it drastically different to how it first was designed to work. It now looks more akin to BIP148, which was AFAICT not how BIP8 was originally intended to work. Perhaps this should be made into its own BIP instead, or make it so it's possible to decide how the LOCKED_IN state should work when designing the softfork. Hampus 2017-07-05 6:10 GMT+02:00 Luke Dashjr via bitcoin-dev < bitcoin-dev@lists.linuxfoundation.org>: > It's not pointless: it's a wake-up call for miners asleep "at the wheel", > to > ensure they upgrade in time. Not having a mandatory signal turned out to > be a > serious bug in BIP 9, and one which is fixed in BIP 148 (and remains a > problem > for BIP 149 as-is). Additionally, it makes the activation decisive and > unambiguous: once the lock-in period is complete, there remains no > question as > to what the correct protocol rules are. > > It also enables deploying softforks as a MASF, and only upgrading them to > UASF > on an as-needed basis. > > Luke > > > On Wednesday 05 July 2017 4:00:38 AM shaolinfry wrote: > > Luke, > > I previously explored an extra state to require signalling before > > activation in an earlier draft of BIP8, but the overall impression I got > > was that gratuitous orphaning was undesirable, so I dropped it. I > > understand the motivation behind it (to ensure miners are upgraded), but > > it's also rather pointless when miners can just fake signal. A properly > > constructed soft fork is generally such that miners have to deliberately > > do something invalid - they cannot be tricked into it... and miners can > > always chose to do something invalid anyway. > > > > > -------- Original Message -------- > > > From: luke@dashjr.org > > > To: bitcoin-dev@lists.linuxfoundation.org, shaolinfry > > > I"ve already opened a PR almost 2 weeks ago > > > to do this and fix the other issues BIP 9 has. > > > https://github.com/bitcoin/bips/pull/550 > > > It just needs your ACK to merge. > > > > > > On Wednesday 05 July 2017 1:30:26 AM shaolinfry via bitcoin-dev wrote: > > >> Some people have criticized BIP9"s blocktime based thresholds arguing > > >> they are confusing (the first retarget after threshold). It is also > > >> vulnerable to miners fiddling with timestamps in a way that could > > >> prevent or delay activation - for example by only advancing the block > > >> timestamp by 1 second you would never meet the threshold (although > this > > >> would come a the penalty of hiking the difficulty dramatically). On > the > > >> other hand, the exact date of a height based thresholds is hard to > > >> predict a long time in advance due to difficulty fluctuations. > However, > > >> there is certainty at a given block height and it"s easy to monitor. > If > > >> there is sufficient interest, I would be happy to amend BIP8 to be > > >> height based. I originally omitted height based thresholds in the > > >> interests of simplicity of review - but now that the proposal has been > > >> widely reviewed it would be a trivial amendment. > _______________________________________________ > bitcoin-dev mailing list > bitcoin-dev@lists.linuxfoundation.org > https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev > --001a114fcfd65f51d60553973ac8 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
From the PR change:

> Miners must= continue setting the bit in LOCKED_IN phase so uptake is visible and ackno= wledged. Blocks without the applicable bit set are invalid during this period
Luke, it seems like the amendments to BIP8 make it drastically diffe= rent to how it first was designed to work.
It now looks more akin to BIP= 148, which was AFAICT not how BIP8 was originally intended to work.
Perhaps this should be made into its own BIP instead, or make it so it= 9;s possible to decide how the LOCKED_IN state should work when designing t= he softfork.

Hampus

2017-07-05 6:10 GMT+02:00 Luke Dashjr via bitcoin-= dev <bitcoin-dev@lists.linuxfoundation.org>:
It's not pointless: it's a w= ake-up call for miners asleep "at the wheel", to
ensure they upgrade in time. Not having a mandatory signal turned out to be= a
serious bug in BIP 9, and one which is fixed in BIP 148 (and remains a prob= lem
for BIP 149 as-is). Additionally, it makes the activation decisive and
unambiguous: once the lock-in period is complete, there remains no question= as
to what the correct protocol rules are.

It also enables deploying softforks as a MASF, and only upgrading them to U= ASF
on an as-needed basis.

Luke


On Wednesday 05 July 2017 4:00:38 AM shaolinfry wrote:
> Luke,
> I previously explored an extra state to require signalling before
> activation in an earlier draft of BIP8, but the overall impression I g= ot
> was that gratuitous orphaning was undesirable, so I dropped it. I
> understand the motivation behind it (to ensure miners are upgraded), b= ut
> it's also rather pointless when miners can just fake signal. A pro= perly
> constructed soft fork is generally such that miners have to deliberate= ly
> do something invalid - they cannot be tricked into it... and miners ca= n
> always chose to do something invalid anyway.
>
> > -------- Original Message --------
> > From: luke@dashjr.org
> > To: bitc= oin-dev@lists.linuxfoundation.org, shaolinfry
> > <shaolinfry@proton= mail.ch> I"ve already opened a PR almost 2 weeks ago
> > to do this and fix the other issues BIP 9 has.
> > https://github.com/bitcoin/bips/pull/550<= br> > > It just needs your ACK to merge.
> >
> > On Wednesday 05 July 2017 1:30:26 AM shaolinfry via bitcoin-dev w= rote:
> >> Some people have criticized BIP9"s blocktime based thres= holds arguing
> >> they are confusing (the first retarget after threshold). It i= s also
> >> vulnerable to miners fiddling with timestamps in a way that c= ould
> >> prevent or delay activation - for example by only advancing t= he block
> >> timestamp by 1 second you would never meet the threshold (alt= hough this
> >> would come a the penalty of hiking the difficulty dramaticall= y). On the
> >> other hand, the exact date of a height based thresholds is ha= rd to
> >> predict a long time in advance due to difficulty fluctuations= . However,
> >> there is certainty at a given block height and it"s easy= to monitor. If
> >> there is sufficient interest, I would be happy to amend BIP8 = to be
> >> height based. I originally omitted height based thresholds in= the
> >> interests of simplicity of review - but now that the proposal= has been
> >> widely reviewed it would be a trivial amendment.
_______________________= ________________________
bitcoin-dev mailing list
bitcoin-dev@lists.= linuxfoundation.org
https://lists.linuxfoundation.org= /mailman/listinfo/bitcoin-dev

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