High Performance, Hyperconverged.
Start by identifying the NVME drive type (“nvme list“) since the NVME drives use the nvme protocol, they will not sshow up in the output of lsscsi Identify NVME Identify the nvme drives using “nvme list” nutanix@NTNX-18SM3E420118-A-CVM:10.56.6.36:~/tmp$ sudo nvme list Node SN Model Version Namespace Usage Format FW Rev/dev/nvme0n1 S3HDNX0KC00137 SAMSUNG MZWLL1T6HEHP-00003 1.2 1 1.60…
Read More →
The real-world achievable SSD performance will vary depending on factors like IO size, queue depth and even CPU clock speed. It’s useful to know what the SSD is capable of delivering in the actual environment in which it’s used. I always start by looking at the performance claimed by the manufacturer. I use these figures…
Read More →The vertica vioperf tool is used to determine whether the storage you are planning on using is fast enough to feed the vertica database. When I initially ran the tool, the IO performance reported by the tool and confirmed by iostat was much lower than I expected for the storage device (a 6Gbit SATA device…
Read More →The fio Pareto parameter allows us to create a workload, which references a very large dataset, but specify a hotspot for the access pattern. Here’s an example using the same setup as the ILM experiment, but using a Pareto value of 0:8. My fio file looks like this.. [global] ioengine=libaio direct=1 time_based norandommap random_distribution=pareto:0.8 The…
Read More →We have started seeing misaligned partitions on Linux guests runnning certain HDFS distributions. How these partitions became mis-aligned is a bit of a mystery, because the only way I know how to do this on Linux is to create a partition using old DOS format like this (using -c=dos and -u=cylinders)
Read More →