Re: [netconf] restconf collections

Robert Varga <nite@hq.sk> Tue, 29 September 2020 23:23 UTC

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To: Martin Björklund <mbj+ietf@4668.se>, kent+ietf@watsen.net
Cc: netconf@ietf.org
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From: Robert Varga <nite@hq.sk>
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Date: Wed, 30 Sep 2020 01:23:49 +0200
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Subject: Re: [netconf] restconf collections
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On 29/09/2020 20:57, Martin Björklund wrote:
> Also, since the main objective is efficient retrieval, "sort-by"
> can perhaps be removed.  Consider large lists in operational state
> that also change often.

+1.

Getting hold of enough state to guarantee stable iteration order can be
done quite efficiently.

Sorting requires touching the data indices at the very least (to
understand that no sorting is needed), potentially a huge
CPU/MEM/network operation at the worst (a.k.a. "establish global order
of entities in a distributed system").

If the criteria is user-specified, the possibility of a DoS becomes very
real -- and hence the question becomes 'can the query be sufficiently
analyzed to reject it early and prevent overloading the system?' :)

Regards,
Robert