> * 2 MB, height 210,000 < 420,000; (when 75% of last 1,000 blocks signal support)

This doesnt give anyone a chance to upgrade and would cause a hard fork the moment a miner created a >1MB block. Flag day (hard fork) upgrades must start the change at a sufficient time in the future (greater than the current block height) to give all nodes the chance to upgrade.

On Fri, Nov 13, 2015 at 3:37 AM, John Sacco via bitcoin-dev <bitcoin-dev@lists.linuxfoundation.org> wrote:
I like your suggestion for the continuity and it gets us up to 2 MB in the shorter term. Also I just noticed the math error. 

Here is a revised spec (incorporating suggestions from Chun Wang):

Specification

* 1 MB, height < 210,000;
* 2 MB, height 210,000 < 420,000; (when 75% of last 1,000 blocks signal support)
* 4 MB, height 420,000 < 630,000; (year 2016)
* 8 MB, height 630,000 < 840,000; (year ~2020)
* 16 MB, height 840,000 < 1,050,000; (year ~2024)
* 32 MB, height >= 1,050,000. (year ~2028)



On Thu, Nov 12, 2015 at 9:56 PM, Chun Wang <1240902@gmail.com> wrote:
How about these specs:
* 1 MB, height < 210000;
* 2 MB, 210000 <= height < 420000;
* 4 MB, 420000 <= height < 630000;
* 8 MB, 630000 <= height < 840000;
* 16 MB, 840000 <= height < 1050000;
* 32 MB, height >= 1050000.


On Fri, Nov 13, 2015 at 7:47 AM, John Sacco via bitcoin-dev
<bitcoin-dev@lists.linuxfoundation.org> wrote:
> Hi Devs,
>
>
> Please consider the draft proposal below for peer review.
>
>
> Thanks,
>
>
> John
>
>
> BIP
>
>   BIP: ?
>
>   Title: Block size doubles at each reward halving with max block size of
> 32M
>
>   Author: John Sacco <johnsock@gmail.com>
>
>   Status: Draft
>
>   Type: Standards Track
>
>   Created: 2015-11-11
>
> Abstract
>
> Change max block size to 2MB at next block subsidy halving, and double the
> block size at each subsidy halving until reaching 32MB.
>
> Copyright
>
> This proposal belongs in the public domain. Anyone can use this text for any
> purpose with proper attribution to the author.
>
> Motivation
>
> 1.    Gradually restores block size to the default 32 MB setting originally
> implemented by Satoshi.
>
> 2.    Initial increase to 2MB at block halving in July 2016 would have
> minimal impact to existing nodes running on most hardware and networks.
>
> 3.    Long term solution that does not make enthusiastic assumptions
> regarding future bandwidth and storage availability estimates.
>
> 4.    Maximum block size of 32MB allows peak usage of ~100 tx/sec by year
> 2031.
>
> 5.    Exercise network upgrade procedure during subsidy reward halving, a
> milestone event with the goal of increasing awareness among miners and node
> operators.
>
> Specification
>
> 1.    Increase the maximum block size to 2MB when block 630,000 is reached
> and 75% of the last 1,000 blocks have signaled support.
>
> 2.    Increase maximum block size to 4MB at block 840,000.
>
> 3.    Increase maximum block size to 8MB at block 1,050,000.
>
> 4.    Increase maximum block size to 16MB at block 1,260,000.
>
> 5.    Increase maximum block size to 32MB at block 1,470,000.
>
> Backward compatibility
>
> All older clients are not compatible with this change. The first block
> larger than 1M will create a network partition excluding not-upgraded
> network nodes and miners.
>
> Rationale
>
> While more comprehensive solutions are developed, an increase to the block
> size is needed to continue network growth. A longer term solution is needed
> to prevent complications associated with additional hard forks. It should
> also increase at a gradual rate that retains and allows a large distribution
> of full nodes.  Scheduling this hard fork to occur no earlier than the
> subsidy halving in 2016 has the goal of simplifying the communication
> outreach needed to achieve consensus, while also providing a buffer of time
> to make necessary preparations.
>
>
> _______________________________________________
> bitcoin-dev mailing list
> bitcoin-dev@lists.linuxfoundation.org
> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
>


_______________________________________________
bitcoin-dev mailing list
bitcoin-dev@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev