Do you have that many queries? You could just review them and your data model to see if there was an error of some kind. How long has it been happening? What changed since it started happening?
Kenneth Brotman From: Subroto Barua [mailto:sbarua...@yahoo.com.INVALID] Sent: Friday, February 01, 2019 10:13 AM To: user@cassandra.apache.org Subject: Re: Help with sudden spike in read requests Vnode is 256 C*: 3.0.15 on m4.4xlarge gp2 vol There are 2 more DCs on bare metal (raid 10 and older machines) attached to this cluster and we have not seen this behavior on on-prem servers If this event is triggered by some bad query/queries, what is the best way to trap it? Subroto On Feb 1, 2019, at 8:55 AM, Kenneth Brotman <kenbrot...@yahoo.com.invalid> wrote: If you had a query that went across the partitions and especially if you had vNodes set high, that would do it. Kenneth Brotman From: Subroto Barua [mailto:sbarua...@yahoo.com.INVALID] Sent: Friday, February 01, 2019 8:45 AM To: User cassandra.apache.org <http://cassandraapache.org> Subject: Help with sudden spike in read requests In our production cluster, we observed sudden spike (over 160 MB/s) in read requests on *all* Cassandra nodes for a very short period (less than a min); this event happens few times a day. I am not able to get to the bottom of this issue, nothing interesting in system.log or from app level; repair was not running Does anyone have any thoughts on what could have triggered this event? Under what condition C* (if it is tied to c*) will trigger this type of event? Thanks! Subroto
