New Project Proposal: The Block GC

Ben Evans benjamin.john.evans at
Mon Apr 2 00:27:03 UTC 2018

Given Oracle’s ongoing chronic under-investment in the Java platform, I
propose that we should fund this via non-traditional means.

We should hold an ICO - selling 1bn Garbage tokens (symbol GBO) to raise
funds for the necessary engineering work.

This will totally not be a security, as the GBO token will convey the right
to not run GC at all, and have it done elsewhere in the network. This is
completely technically feasible & not something we made up. Also because we
say that it isn’t a security, the SEC is totally fine with that.

I propose a starting value of 1 GBO == 1 tulip bulb, or 2.7 Updog.

I can probably have GBO listed on major crypto currency exchanges by Monday


On Sun, 1 Apr 2018 at 03:35, Magnus Ihse Bursie <
magnus.ihse.bursie at> wrote:

> I hereby propose the creation of the Block GC Project with myself
> (Magnus Ihse Bursie) as the Lead and the Build Group as the sponsoring
> group.
> In accordance with the OpenJDK guidelines [1], this project will provide
> the Block GC, a creative new approach of handling GC mis-optimization.[2]
> The Block GC, also known as the Block Chain GC, is an innovative new
> system for Garbage Collection. It is a well-known fact that even though
> the JVM can be fine-tuned to employ an optimal GC method for a specific
> payload, most users do not bother to do so, or lack the technical skills
> needed to select the proper GC. The Block GC is a "parasitic" GC, in
> that it does not provide a separate GC system of it own, but instead
> selects the most optimal GC for each individual payload.
> As a unique feature, the Block GC will measure and accurately calculate
> the improvement provided by selecting the optimal GC method, compared to
> the GC previously selected. Let T_gc_def be the time the user
> application is stopped during the GC for the default GC settings, and
> let T_gc_opt be the corresponding time using the optimal GC method
> selected by the Block GC. The difference T_gc_def - T_gc_opt is the
> improvement in pausetime provided by the Block GC, and is known as the
> "block gain".
> The block gain can be seen as a hidden resource, available for free from
> the user of the JRE. After the GC has finished, the JRE can use the time
> provided by the block gain, with the user threads still suspended,
> without the application suffering performance regressions. In the
> initial implementation of the Block GC, the block gain was just used to
> let the JVM sleep for an amount of time corresponding to the block gain.
> This gave us a simple way to save processor cycles, and hence energy,
> thus providing a simple way for the Java user to help fight climate
> change without even noticing it.
> While a noble goal, this does not really makes business sense. In the
> updated version of the Block GC, which we propose to be added as the
> default GC in JDK 11, the block gain is instead used to calculate hash
> values for popular cryptocurrencies, a.k.a. "bitcoin mining". Our
> estimates show that this can generate a significant amount of revenue;
> with a projected ~50 M downloads of JDK 11, running typical workloads,
> and with typical values for GC settings (default or misconfigured),
> $50k/day for all OpenJDK installations worldwide is not unreasonable.
> This is a pure win-win scenario. The user will not notice any
> performance regression compared to the previous GC settings, and the
> cryptocurrency account proprietor will benefit fiscally.
> The user can set their own blockchain account, instead of the default,
> by issuing this command:
>     java -XX:UnlockDangerousOptions
> -XX:UnsupportedGCOption=new_provider_config:<path to config file>
> where <path to config file> points to a configuration file in ASN.1
> format describing the blockchain account. We hope to finish the
> documentation of this file in time for the release, but if not done, it
> will not be considered a release blocker.
> If a user override is not provided as above, by default, the revenue
> extracted by the Block GC miner will be stored in the Block GC Project
> account. This revenue will be divided as follows: 90% will go to the
> initial committers of the Block GC Project, and 10% will go to the
> OpenJDK community.
> The first installment of the 10% payment to the OpenJDK comminuty will
> be issued exactly one year from now, on April 1st 2019.[3]
> A preview of the Block GC can be found here:
> The initial Committers will be: Magnus Ihse Bursie, Satoshi Nakamoto and
> P. T. Barnum.
> /Magnus
> [1]
> [2]
> [3]

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