Data Access Applications
Hive Query Recommendation
Queries are slow because of several reasons, some of those are overlooked several of the times. Following list of recommendations are some automatic recommendations that get generated:
hive.auto.convert.join=true; hive.cbo.enable=true; hive.vectorized.execution.enabled=true; hive.groupby.skewindata=true;
Container Size Recommendations
Container sizing is one of the most difficult aspect of ongoing operations. The following recommendations allow system administrators to identify jobs that are wasting resources to correct at
- Setting at a queue level
- Individual level
Stats Generation Recommendation
Upon observing the system for a certain amount of time, Acceldata can predict the time of availability of resources on the system and recommend when the stats gather should be run on Hive table.
This enables the CBO to act and allows queries to perform better.
Users unknowingly waste a lot of their executor resources. Identifying these scenarios are very difficult in real-time with OEM/Community tools.
Here is a brief demo of exploring the execution of Spark Jobs and the identification that shows the amount of executor that is wasted. Such Users and Applications also qualify as Rogue users.
Spark Executor Wastage
Post this identification, the following courses of actions are possible:
- Review of the Spark program to shift compute to Executor as opposed to the Driver
- Highlighting the areas of code which are either I/O intensive or have taken a lot of time
- Along with the above two, it also shows the yarn diagnostics messages for additional guidance
Hbase Table Hotspotting Fixes
Rowkeys when are not created correctly cause Region and Table hotspotting. This would need a re-design of the row-key, which is discussed in detail here