[
https://issues.apache.org/jira/browse/CASSANDRA-9318?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15375012#comment-15375012
]
Jonathan Ellis commented on CASSANDRA-9318:
-------------------------------------------
bq. Hints are not a solution for chronically overloaded clusters where clients
ingest faster than replicas can consume
That is the situation I describe in scenario 3, which is the problem I opened
this ticket to solve. So, I agree that scenario is a problem, but I don't
think this proposal is a very good solution for that, and it causes other
problems in the other two (non-global-overload) scenarios.
bq. I think we do solve that, actually in a better way, which takes into
consideration all replicas, not just the coordinator capacity of acting as a
buffer, unless I'm missing a specific case you're referring to?
I honestly don't see what is "better" about a "slow every write down to the
speed of the slowest, possibly sick, replica" approach. Defining a simple high
water mark on requests in flight should be much simpler without the negative
side effects.
> Bound the number of in-flight requests at the coordinator
> ---------------------------------------------------------
>
> Key: CASSANDRA-9318
> URL: https://issues.apache.org/jira/browse/CASSANDRA-9318
> Project: Cassandra
> Issue Type: Improvement
> Components: Local Write-Read Paths, Streaming and Messaging
> Reporter: Ariel Weisberg
> Assignee: Sergio Bossa
> Attachments: 9318-3.0-nits-trailing-spaces.patch, backpressure.png,
> limit.btm, no_backpressure.png
>
>
> It's possible to somewhat bound the amount of load accepted into the cluster
> by bounding the number of in-flight requests and request bytes.
> An implementation might do something like track the number of outstanding
> bytes and requests and if it reaches a high watermark disable read on client
> connections until it goes back below some low watermark.
> Need to make sure that disabling read on the client connection won't
> introduce other issues.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
