Dse on Random Ramblings

Getting Index Size in DSE Search

Thu, 24 Mar 2022 02:00:00 +0000

Getting Index Size in DSE Search

Applies to DSE Search versions 3.2 to 6.8

For some reason finding this information is dreadfully stupidly hard and I finally decided to write it down myself since I own it and someone may benefit from it some day. There are three ways that I know of (I am sure there is a JMX way I just do not happen to know it atm)

Detecting and dealing with backpressure in DSE 6.x

Wed, 28 Jul 2021 08:11:00 +0000

Detecting and dealing with backpressure in DSE 6.x

Several years ago DataStax change DataStax Enterprise from a version of Cassandra with some closed source plugins and a handful of fixes most of which were backports of fixes in very old versions, to a fundamentally different architecture. This new architecure we will refer to as TPC, however, there were also several internals that were changed that may have relied or depended on TPC but were not actually themselves part of TPC.

Tuning Indexing Speed in DSE Search 5.x

Fri, 26 Feb 2021 00:00:00 +0000

Tuning Indexing Speed in DSE Search 5.x

What follows is a summary of the things you need to consider dealing with indexing speed problems in DSE 5.x (note the model of indexing is wildly different in DSE 6.x and will not apply, I will have a guide on that soon).

Dropped Mutations

With Solr 5.x dropped mutations have three causes over regular Cassandra:

During the merging of Solr indexes, you can “stall” due to configuration limits.
By default, Solr indexing is very aggressive and can starve IO, all activities will slow, and the cluster may experience dropped mutations.
Back pressure leading to drops. If QueueWeight in the com.datastax.bdp.search.keyspace_name.table_name.IndexPool MBean is greater than back_pressure_threshold_per_core, back pressure is happening.

To minimize IO contention and merge stalling do the following steps: