summaryrefslogtreecommitdiff
path: root/b8/844323d248a4864259ba4fc33a092634d3ba7c
blob: 7d7bf437bdb5ad0fdc45b00142d210138b024b6f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
Return-Path: <luke@dashjr.org>
Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org
	[172.17.192.35])
	by mail.linuxfoundation.org (Postfix) with ESMTPS id 0A678959
	for <bitcoin-dev@lists.linuxfoundation.org>;
	Wed, 31 May 2017 04:15:39 +0000 (UTC)
X-Greylist: from auto-whitelisted by SQLgrey-1.7.6
Received: from zinan.dashjr.org (zinan.dashjr.org [192.3.11.21])
	by smtp1.linuxfoundation.org (Postfix) with ESMTP id 67FFD144
	for <bitcoin-dev@lists.linuxfoundation.org>;
	Wed, 31 May 2017 04:15:38 +0000 (UTC)
Received: from ishibashi.localnet (unknown
	[IPv6:2001:470:5:265:a45d:823b:2d27:961c])
	(Authenticated sender: luke-jr)
	by zinan.dashjr.org (Postfix) with ESMTPSA id 2343138A0093;
	Wed, 31 May 2017 04:14:28 +0000 (UTC)
X-Hashcash: 1:25:170531:bitcoin-dev@lists.linuxfoundation.org::twnobufcbaoHyb0M:a3kBF
X-Hashcash: 1:25:170531:jtimon@jtimon.cc::B3ggVQJHPAh0RfB9:KhF1
X-Hashcash: 1:25:170531:macwhyte@gmail.com::JItRFthD9Vy9AgHg:hW3PI
From: Luke Dashjr <luke@dashjr.org>
To: bitcoin-dev@lists.linuxfoundation.org,
	Jorge =?iso-8859-1?q?Tim=F3n?= <jtimon@jtimon.cc>
Date: Wed, 31 May 2017 04:14:25 +0000
User-Agent: KMail/1.13.7 (Linux/4.9.16-gentoo; KDE/4.14.29; x86_64; ; )
References: <201705232023.40588.luke@dashjr.org>
	<CAH+Axy5yYQywpy0s9pBZt_fNoLPpWfra-cU9HrUwH71GDOchsQ@mail.gmail.com>
	<CABm2gDoJ7S3pjdjdbKZ4-EuVXnEOj-gEPzSEvUGdtYovZaNK=g@mail.gmail.com>
In-Reply-To: <CABm2gDoJ7S3pjdjdbKZ4-EuVXnEOj-gEPzSEvUGdtYovZaNK=g@mail.gmail.com>
X-PGP-Key-Fingerprint: E463 A93F 5F31 17EE DE6C 7316 BD02 9424 21F4 889F
X-PGP-Key-ID: BD02942421F4889F
X-PGP-Keyserver: hkp://pgp.mit.edu
MIME-Version: 1.0
Content-Type: Text/Plain;
  charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
Message-Id: <201705310414.26724.luke@dashjr.org>
X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00,RCVD_IN_DNSWL_MED,
	RP_MATCHES_RCVD autolearn=ham version=3.3.1
X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on
	smtp1.linux-foundation.org
Subject: Re: [bitcoin-dev] Hypothetical 2 MB hardfork to follow BIP148
X-BeenThere: bitcoin-dev@lists.linuxfoundation.org
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: Bitcoin Protocol Discussion <bitcoin-dev.lists.linuxfoundation.org>
List-Unsubscribe: <https://lists.linuxfoundation.org/mailman/options/bitcoin-dev>,
	<mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=unsubscribe>
List-Archive: <http://lists.linuxfoundation.org/pipermail/bitcoin-dev/>
List-Post: <mailto:bitcoin-dev@lists.linuxfoundation.org>
List-Help: <mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=help>
List-Subscribe: <https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev>,
	<mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=subscribe>
X-List-Received-Date: Wed, 31 May 2017 04:15:39 -0000

On Wednesday 31 May 2017 1:22:44 AM Jorge Tim=F3n via bitcoin-dev wrote:
> Why is it
> https://github.com/bitcoin/bitcoin/blob/master/src/validation.cpp#L1661
> not enough at this point?
> Why the need for a transaction size limit?

Because the bottleneck is hashing the transaction, which costs (in CPU time=
)=20
based on its size. Maybe it would make sense to factor sigops into the limi=
t,=20
though?

On Wednesday 31 May 2017 1:09:26 AM Jean-Paul Kogelman via bitcoin-dev wrot=
e:
> On May 30, 2017, at 4:50 PM, James MacWhyte wrote:
> > Add a transaction-size limit of, say, 10kb and the quadratic hashing
> > problem is a non-issue. Donezo.
>
> That would invalidate any pre-signed transactions that are currently out
> there. You can't just change the rules out from under people.

Make it 100kB and I think we'd be okay. Those have always been policy-
forbidden so there should be no expectation they'd be acceptable in the=20
future.

While we're at it, I suggest also specifying a minimum transaction size as=
=20
well. The raw minimum possible is 60 bytes, but any sane output would need =
at=20
least a hash, so I'd say make the minimum be 8 (60 + 160-bit hash) bytes?

Luke