Re: [Sidrops] notes on rsync --delete (rrdp withdraw), and garbage collection

Rob Austein <sra@hactrn.net> Mon, 16 November 2020 04:18 UTC

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Date: Sun, 15 Nov 2020 23:18:07 -0500
From: Rob Austein <sra@hactrn.net>
To: Job Snijders <job@ntt.net>
Cc: sidrops@ietf.org
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Subject: Re: [Sidrops] notes on rsync --delete (rrdp withdraw), and garbage collection
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[Apologies for belated response, saw this while catching before
today's meeting (for some definition of "today")]

Job, I agree that flushing data solely because rsync or RRDP said to
do so is a bad idea, but I think that outlawing rsync --delete or RRDP
withdraw is going a bit overboard in the other direction.

The operative word here is "solely".  At least in my implementation,
rsync/RRDP deletion only remove data from the pre-validation cache;
there's a separate cache of previously-validated data, and I use both
of them when constructing the output of the current validation cycle.

End result is that we only gc objects that have both been deleted and
have failed to pass validation, which (still) seems about right to me.