
On Ink Shortages - rbanffy
http://ellismichael.com/blog/2017/10/20/on-ink-shortages/
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mjevans
Decentralized decision making processes are difficult, and this (through a
'human example story') shows the assumptions of state that can make in person
processes seem easier than they actually are.

The solution of recording relativistic epochs for each voting member (name and
'year' (version)) seems like part of the full solution. An enumeration of
current members (and their version) as well as a careful protocol for members
to be modified (including add, remove, and increment version) seems to be
required.

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yuliyp
The race described here sounds pretty similar to a type of cache consistency
race: Client X reads a complex value from a database, does some calculation,
and writes the result in a cache. Client Y updates something that should
invalidate the calculation. When Client Y tries to invalidate the cache, they
don't yet see Client X's entry, which will then appear slightly later. Now a
stale value persists in the cache.

The assumption is that after the invalidate done by Y, the cache cannot
contain a value that missed Y's update is incorrect.

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xchaotic
Byzantine Paxos ;) It does make me wonder how much failure do we design to
tolerate. Many modern systems are designed for five nines availability -
99.999% of the time. A partition like the one described here is rather
unlikely and having more data on every message might pretty inefficient for
the 99.999%+ of cases (not every failures will result in a partition like
this)

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justinjlynn
Request re-title to include: [Byzantine Paxos].

