Hi Team,

We are heavy users of Cassandra at a pretty big bank.  Security measures
require us to constantly refresh our C* nodes every x number of days.  We
normally do this in a rolling fashion, taking one node down at a time and
then refreshing it with a new instance.  This process has been working for
us great for the past few years.

However, we recently started having issues when a newly refreshed instance
comes back online, our automation waits a few minutes for the node to
become "ready (UN)" and then moves on to the next node.  The problem that
we are facing is that when the node is ready, the chunk cache is still
empty so when the node starts accepting new connections, queries that go to
take much longer to respond and this causes errors for our apps.

I was thinking that it would be great if we had a nodetool command that
would allow us to prefetch a certain table or a set of tables to preload
the chunk cache.  Then we could simply add another check (nodetool info?),
to ensure that the chunk cache has been preloaded enough to handle queries
to this particular node.

Would love to hear others' feedback on the feasibility of this idea.


Reply via email to