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MemSQL performance issues


I have a single node MemSQL install with one master aggregator and two leaves (all on a single box). The machine has 2 cores, 16Gb RAM, and MemSQL columnstore data is ~7Gb (coming from 21Gb CSV). When running queries on the data, memory usage caps at ~2150Mb (11Gb sitting free). I've configured both leaves to have maximum_memory = 7000 in the memsql.cnf files for both nodes (memsql-optimize does similar). During query execution, the master aggregator sits at 100% CPU, with the leaves 0-8% CPU.

This does not seems like an efficient use of system resources, but I'm not sure what I can do to configure the system or MemSQL to make more efficient use of CPU or memory. Any help would be greatly appreciated!


Solution

  • My database was coming from some other place than the current memsql install (perhaps an older cluster configuration) despite there only being a single memsql cluster on the machine. Looking at the Databases section in the Web UI was displaying no databases/tables, but my queries were succeeded with the expected answers.

    drop database/reload from CSV managed to remedy the situation. All core threads are now used during query.