Matt Corallo [ARCHIVE] on Nostr: đ Original date posted:2021-09-01 đ Original message: Please be careful ...
đ
Original date posted:2021-09-01
đ Original message:
Please be careful accepting the faulty premise that the proposed algorithm is âoptimalâ. It is optimal under a specific heuristic used to approximate what the user wants. In reality, there are a ton of different things to balance, from CLTV to feed to estimated failure probability calculated from node online percentages at-open liquidity, and even fees. There is no such thing as âoptimalâ, only heuristics for how to balance these things into a score that you can feed into a routing algorithm.
> Do we really want users to solve an NP-hard problem when they wish to find a cheap way of paying each other on the Lightning Network?
I find this framing sufficiently insulting to the serious discussion people have had on this topic that Iâm not really sure where to go from here aside from ignoring it.
> On Aug 31, 2021, at 03:35, Orfeas Stefanos Thyfronitis Litos <o.thyfronitis at ed.ac.uk> wrote:
>
> ï»żHi list,
>
> On 8/31/21 5:01 AM, Anthony Towns wrote:
>>> "Do we really want users to solve an NP-hard problem when
>>> they wish to find a cheap way of paying each other on the Lightning Network?"
>> FWIW, my answer to this is "sure, if that's the way it turns out".
>>
>> Another program which solves an NP-hard problem every time it runs is
>> "apt-get install".
>> [I]f it fails too often,
>> you re-analyse what's going on manually and add a new heuristic to cope
>> with it.
> I've been following the conversation with interest and I acknowledge this is a thorny issue.
>
> I am a bit worried with a path which relies on constantly finding new heuristics to approximate a solution to an NP-hard problem:
> * It allows too much room for nonconstructive disagreement between LN developers in the future.
> - In a worst case scenario, all implementations end up using different, incompatible heuristics because each group of developers thinks that they have the best one, leading to a suboptimal performance for everyone. Heuristics are less of an exact science after all.
> * It makes the job of node operators less predictable, since it would depend more on the decisions of said developers with no guarantee of convergence to a single solution.
> - Node operators may perceive this as loss of decentralization to the developers.
>
> Such an approach is much more suitable to debian, since they have full control and a complete view over their "network" of packages, as opposed to LN, which is decentralized, nodes come and go at will and they can be private (even from developers!).
>
> Best,
> Orfeas
> The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336. Is e buidheann carthannais a thâ ann an Oilthigh DhĂčn Ăideann, clĂ raichte an Alba, Ă ireamh clĂ raidh SC005336.
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> Lightning-dev at lists.linuxfoundation.org
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đ Original message:
Please be careful accepting the faulty premise that the proposed algorithm is âoptimalâ. It is optimal under a specific heuristic used to approximate what the user wants. In reality, there are a ton of different things to balance, from CLTV to feed to estimated failure probability calculated from node online percentages at-open liquidity, and even fees. There is no such thing as âoptimalâ, only heuristics for how to balance these things into a score that you can feed into a routing algorithm.
> Do we really want users to solve an NP-hard problem when they wish to find a cheap way of paying each other on the Lightning Network?
I find this framing sufficiently insulting to the serious discussion people have had on this topic that Iâm not really sure where to go from here aside from ignoring it.
> On Aug 31, 2021, at 03:35, Orfeas Stefanos Thyfronitis Litos <o.thyfronitis at ed.ac.uk> wrote:
>
> ï»żHi list,
>
> On 8/31/21 5:01 AM, Anthony Towns wrote:
>>> "Do we really want users to solve an NP-hard problem when
>>> they wish to find a cheap way of paying each other on the Lightning Network?"
>> FWIW, my answer to this is "sure, if that's the way it turns out".
>>
>> Another program which solves an NP-hard problem every time it runs is
>> "apt-get install".
>> [I]f it fails too often,
>> you re-analyse what's going on manually and add a new heuristic to cope
>> with it.
> I've been following the conversation with interest and I acknowledge this is a thorny issue.
>
> I am a bit worried with a path which relies on constantly finding new heuristics to approximate a solution to an NP-hard problem:
> * It allows too much room for nonconstructive disagreement between LN developers in the future.
> - In a worst case scenario, all implementations end up using different, incompatible heuristics because each group of developers thinks that they have the best one, leading to a suboptimal performance for everyone. Heuristics are less of an exact science after all.
> * It makes the job of node operators less predictable, since it would depend more on the decisions of said developers with no guarantee of convergence to a single solution.
> - Node operators may perceive this as loss of decentralization to the developers.
>
> Such an approach is much more suitable to debian, since they have full control and a complete view over their "network" of packages, as opposed to LN, which is decentralized, nodes come and go at will and they can be private (even from developers!).
>
> Best,
> Orfeas
> The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336. Is e buidheann carthannais a thâ ann an Oilthigh DhĂčn Ăideann, clĂ raichte an Alba, Ă ireamh clĂ raidh SC005336.
> _______________________________________________
> Lightning-dev mailing list
> Lightning-dev at lists.linuxfoundation.org
> https://lists.linuxfoundation.org/mailman/listinfo/lightning-dev