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How can QuasarDB utilize Mellanox VMA and how should it be configured?

Is there a configuration option or other steps necessary to enable the VMA integration?

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To use VMA with QuasarDB you need to install the VMA library on your system. The instructions are available here:

http://www.mellanox.com/page/software_vma?mtag=vma

Then, you need to use LD_PRELOAD environment variable to make sure VMA is loaded before QuasarDB:

$ LD_PRELOAD=libvma.so /usr/local/bin/qdbd -c /etc/qdb/qdbd.cfg

Assuming you have have the QuasarDB daemon installed in /usr/local/bin and the configuration file in /etc/qdb/qdbd.cfg.

You also need to use LD_PRELOAD before running the program using the libqdb_api library, as both the client and the server should leverage VMA when available for the lowest latency and the best performance.

If you program is "my_program", this means

$ LD_PRELOAD=libvma.so ./my_program

This should immediately yield improved latency and bandwidth.

If you are using a NUMA machine, you may need to play with theĀ VMA_INTERNAL_T
HREAD_AFFINITY parameter.

The VMA installation guide, available at the above address, contains further details.