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0 pointsshin_lao11y ago0 comments

Partitions are rare relative to other events, and I was quoting Eric Brewer, the author of the CAP theorem.

If you have one partition per day (which is very often) but do 100,000 request per seconds: partitions are rare.

10 seconds is hardly a partition as it is below the default TCP timeout (one minute).

Also, while you can't access the partitioned area, you might have nodes outside that area.

So these nodes can't access the partition and you don't have any conflict.

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2 comments · 2 top-level

yummyfajitas11y ago

10 seconds/day breaks 3 9's. The fact that this might be below the TCP timeout is irrelevant, that's almost certainly NOT the timeout that will be considered as unavailability. E.g., suppose you are delivering an advertising tag. Unavailable means > 200ms.

So these nodes can't access the partition and you don't have any conflict.

Conflict comes when you reconnect.

_benedict11y ago

The TCP timeout is kind of irrelevant if your application defined timeout is lower. Cassandra's default timeout is 10s, but in practice most users expect their responses in less than a second.

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