public inbox for bitcoindev@googlegroups.com
 help / color / mirror / Atom feed
From: Jim Phillips <jim@ergophobia.org>
To: Matt Whitlock <bip@mattwhitlock.name>
Cc: Bitcoin Dev <bitcoin-development@lists.sourceforge.net>
Subject: Re: [Bitcoin-development] A suggestion for reducing the size of the UTXO database
Date: Sun, 10 May 2015 07:11:53 -0500	[thread overview]
Message-ID: <CANe1mWxfjTOtgKJ=1MrvLQusoJw6Ecyk+aLoN7JUaVPsyp9S8g@mail.gmail.com> (raw)
In-Reply-To: <2114827.D6GUhXtGkV@crushinator>

[-- Attachment #1: Type: text/plain, Size: 4363 bytes --]

I feel your pain. I've had the same thing happen to me in the past. And I
agree it's more likely to occur with my proposed scheme but I think with HD
wallets there will still be UTXOs left unspent after most transactions
since, for privacy sake it's looking for the smallest set of addresses that
can be linked.
On May 9, 2015 9:11 PM, "Matt Whitlock" <bip@mattwhitlock.name> wrote:

> Minimizing the number of UTXOs in a wallet is sometimes not in the best
> interests of the user. In fact, quite often I've wished for a configuration
> option like "Try to maintain _[number]_ UTXOs in the wallet." This is
> because I often want to make multiple spends from my wallet within one
> block, but spends of unconfirmed inputs are less reliable than spends of
> confirmed inputs, and some wallets (e.g., Andreas Schildbach's wallet)
> don't even allow it - you can only spend confirmed UTXOs. I can't tell you
> how aggravating it is to have to tell a friend, "Oh, oops, I can't pay you
> yet. I have to wait for the last transaction I did to confirm first." All
> the more aggravating because I know, if I have multiple UTXOs in my wallet,
> I can make multiple spends within the same block.
>
>
> On Saturday, 9 May 2015, at 12:09 pm, Jim Phillips wrote:
> > Forgive me if this idea has been suggested before, but I made this
> > suggestion on reddit and I got some feedback recommending I also bring it
> > to this list -- so here goes.
> >
> > I wonder if there isn't perhaps a simpler way of dealing with UTXO
> growth.
> > What if, rather than deal with the issue at the protocol level, we deal
> > with it at the source of the problem -- the wallets. Right now, the
> typical
> > wallet selects only the minimum number of unspent outputs when building a
> > transaction. The goal is to keep the transaction size to a minimum so
> that
> > the fee stays low. Consequently, lots of unspent outputs just don't get
> > used, and are left lying around until some point in the future.
> >
> > What if we started designing wallets to consolidate unspent outputs? When
> > selecting unspent outputs for a transaction, rather than choosing just
> the
> > minimum number from a particular address, why not select them ALL? Take
> all
> > of the UTXOs from a particular address or wallet, send however much needs
> > to be spent to the payee, and send the rest back to the same address or a
> > change address as a single output? Through this method, we should wind up
> > shrinking the UTXO database over time rather than growing it with each
> > transaction. Obviously, as Bitcoin gains wider adoption, the UTXO
> database
> > will grow, simply because there are 7 billion people in the world, and
> > eventually a good percentage of them will have one or more wallets with
> > spendable bitcoin. But this idea could limit the growth at least.
> >
> > The vast majority of users are running one of a handful of different
> wallet
> > apps: Core, Electrum; Armory; Mycelium; Breadwallet; Coinbase; Circle;
> > Blockchain.info; and maybe a few others. The developers of all these
> > wallets have a vested interest in the continued usefulness of Bitcoin,
> and
> > so should not be opposed to changing their UTXO selection algorithms to
> one
> > that reduces the UTXO database instead of growing it.
> >
> > >From the miners perspective, even though these types of transactions
> would
> > be larger, the fee could stay low. Miners actually benefit from them in
> > that it reduces the amount of storage they need to dedicate to holding
> the
> > UTXO. So miners are incentivized to mine these types of transactions
> with a
> > higher priority despite a low fee.
> >
> > Relays could also get in on the action and enforce this type of behavior
> by
> > refusing to relay or deprioritizing the relay of transactions that don't
> > use all of the available UTXOs from the addresses used as inputs. Relays
> > are not only the ones who benefit the most from a reduction of the UTXO
> > database, they're also in the best position to promote good behavior.
> >
> > --
> > *James G. Phillips IV*
> > <https://plus.google.com/u/0/113107039501292625391/posts>
> >
> > *"Don't bunt. Aim out of the ball park. Aim for the company of
> immortals."
> > -- David Ogilvy*
> >
> >  *This message was created with 100% recycled electrons. Please think
> twice
> > before printing.*
>

[-- Attachment #2: Type: text/html, Size: 5062 bytes --]

  reply	other threads:[~2015-05-10 12:12 UTC|newest]

Thread overview: 45+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-05-09 17:09 [Bitcoin-development] A suggestion for reducing the size of the UTXO database Jim Phillips
2015-05-09 18:45 ` Peter Todd
2015-05-09 19:02   ` Jim Phillips
2015-05-09 19:00 ` Andreas Schildbach
2015-05-09 19:05   ` Jim Phillips
2015-05-09 19:06   ` Pieter Wuille
2015-05-09 19:16     ` Jim Phillips
2015-05-09 19:43       ` Ross Nicoll
     [not found] ` <3862E01F-FD0F-48F5-A6D9-F8E0FB0AB68F@newcastle.ac.uk>
     [not found]   ` <CANe1mWys1gAO1CgPEpD7rdtXF2KYfvXA6bc0q-rAzg9xOFc-5A@mail.gmail.com>
     [not found]     ` <8029969D-FD22-43F7-930D-CEC7A87CEAD5@newcastle.ac.uk>
2015-05-09 19:28       ` Jim Phillips
2015-05-10  2:11 ` Matt Whitlock
2015-05-10 12:11   ` Jim Phillips [this message]
2015-05-25 18:41   ` Mike Hearn
2015-05-25 20:03     ` Matt Whitlock
2015-05-25 20:29       ` Andreas Schildbach
2015-05-25 21:05         ` Peter Todd
2015-05-26 12:40           ` Andreas Schildbach
2015-05-25 21:14         ` Warren Togami Jr.
2015-05-25 21:12       ` Mike Hearn
2015-05-10 13:35 ` Bob McElrath
2015-05-10 14:33   ` Jeff Garzik
2015-05-10 14:42     ` Bob McElrath
2015-05-12 19:50 ` Danny Thorpe
2015-05-25 18:44 ` Mike Hearn
2015-05-25 21:26   ` Peter Todd
2015-05-25 22:03     ` Mike Hearn
2015-05-26  0:10       ` [Bitcoin-development] Cost savings by using replace-by-fee, 30-90% Peter Todd
2015-05-26 18:22         ` Danny Thorpe
2015-05-26 18:38           ` Allen Piscitello
2015-05-26 18:42           ` Aaron Voisine
2015-05-26 18:47           ` Adam Back
2015-05-26 20:18           ` Matt Whitlock
2015-05-26 20:30         ` joliver
2015-05-26 20:56           ` Mark Friedenbach
2015-05-26 21:29           ` s7r
2015-05-26 22:06             ` Adam Back
2015-05-27  1:25             ` Peter Todd
2015-05-27 19:28               ` s7r
2015-05-26 22:29           ` Jeff Garzik
2015-05-09 19:25 [Bitcoin-development] A suggestion for reducing the size of the UTXO database Raystonn
2015-05-09 19:33 ` Jim Phillips
2015-05-09 19:43 Raystonn
2015-05-09 19:52 ` Jim Phillips
2015-05-09 20:20 Raystonn
2015-05-09 20:38 ` Pieter Wuille
2015-05-09 21:11   ` Jim Phillips

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to='CANe1mWxfjTOtgKJ=1MrvLQusoJw6Ecyk+aLoN7JUaVPsyp9S8g@mail.gmail.com' \
    --to=jim@ergophobia.org \
    --cc=bip@mattwhitlock.name \
    --cc=bitcoin-development@lists.sourceforge.net \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox