📅 Original date posted:2018-05-18
📝 Original message:Another parameter which heavily affects filter size is the false positive
rate which is empirically set
<https://github.com/bitcoin/bips/blob/master/bip-0158.mediawiki#construction>;
to 2^-20
The BIP recall some go code
<https://github.com/Roasbeef/bips/blob/83b83c78e189be898573e0bfe936dd0c9b99ecb9/gcs_light_client/gentestvectors.go>;
for how the parameter has been selected which I can hardly understand and
run, it's totally my fault but if possible I would really like more details
on the process, like charts and explanations (for example, which is the
number of elements to search for which the filter has been optimized for?)
Instinctively I feel 2^-20 is super low and choosing a lot higher alpha
will shrink the total filter size by gigabytes at the cost of having to
wastefully download just some megabytes of blocks.
2018-05-17 18:36 GMT+02:00 Gregory Maxwell via bitcoin-dev <
bitcoin-dev at lists.linuxfoundation.org>:
> On Thu, May 17, 2018 at 3:25 PM, Matt Corallo via bitcoin-dev
> <bitcoin-dev at lists.linuxfoundation.org> wrote:
> > I believe (1) could be skipped entirely - there is almost no reason why
> > you'd not be able to filter for, eg, the set of output scripts in a
> > transaction you know about
>
> I think this is convincing for the txids themselves.
>
> What about also making input prevouts filter based on the scriptpubkey
> being _spent_? Layering wise in the processing it's a bit ugly, but
> if you validated the block you have the data needed.
>
> This would eliminate the multiple data type mixing entirely.
> _______________________________________________
> bitcoin-dev mailing list
> bitcoin-dev at lists.linuxfoundation.org
> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
>
--
Riccardo Casatta - @RCasatta <https://twitter.com/RCasatta>;
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Riccardo Casatta [ARCHIVE] /
npub13t…yxl7q
2023-06-07 18:12:18
in reply to nevent1q…ps2k
Author Public Key
npub13t8gempry5dh8dkjw2m9wc0j4wu5kxlk9jxtwf24350fx2gtlqksmyxl7qPublished at
2023-06-07 18:12:18Event JSON
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"pubkey": "8ace8cec23251b73b6d272b65761f2abb94b1bf62c8cb725558d1e93290bf82d",
"created_at": 1686161538,
"kind": 1,
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"content": "📅 Original date posted:2018-05-18\n📝 Original message:Another parameter which heavily affects filter size is the false positive\nrate which is empirically set\n\u003chttps://github.com/bitcoin/bips/blob/master/bip-0158.mediawiki#construction\u003e\nto 2^-20\nThe BIP recall some go code\n\u003chttps://github.com/Roasbeef/bips/blob/83b83c78e189be898573e0bfe936dd0c9b99ecb9/gcs_light_client/gentestvectors.go\u003e\nfor how the parameter has been selected which I can hardly understand and\nrun, it's totally my fault but if possible I would really like more details\non the process, like charts and explanations (for example, which is the\nnumber of elements to search for which the filter has been optimized for?)\n\nInstinctively I feel 2^-20 is super low and choosing a lot higher alpha\nwill shrink the total filter size by gigabytes at the cost of having to\nwastefully download just some megabytes of blocks.\n\n\n2018-05-17 18:36 GMT+02:00 Gregory Maxwell via bitcoin-dev \u003c\nbitcoin-dev at lists.linuxfoundation.org\u003e:\n\n\u003e On Thu, May 17, 2018 at 3:25 PM, Matt Corallo via bitcoin-dev\n\u003e \u003cbitcoin-dev at lists.linuxfoundation.org\u003e wrote:\n\u003e \u003e I believe (1) could be skipped entirely - there is almost no reason why\n\u003e \u003e you'd not be able to filter for, eg, the set of output scripts in a\n\u003e \u003e transaction you know about\n\u003e\n\u003e I think this is convincing for the txids themselves.\n\u003e\n\u003e What about also making input prevouts filter based on the scriptpubkey\n\u003e being _spent_? Layering wise in the processing it's a bit ugly, but\n\u003e if you validated the block you have the data needed.\n\u003e\n\u003e This would eliminate the multiple data type mixing entirely.\n\u003e _______________________________________________\n\u003e bitcoin-dev mailing list\n\u003e bitcoin-dev at lists.linuxfoundation.org\n\u003e https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev\n\u003e\n\n\n\n-- \nRiccardo Casatta - @RCasatta \u003chttps://twitter.com/RCasatta\u003e\n-------------- next part --------------\nAn HTML attachment was scrubbed...\nURL: \u003chttp://lists.linuxfoundation.org/pipermail/bitcoin-dev/attachments/20180518/fe07e012/attachment.html\u003e",
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