n0derunner

    fio versions < 3.3 may show inflated random write performance

    Published: (Updated: ) in fio, Storage Performance, , by gary. Leave a Comment on fio versions < 3.3 may show inflated random write performance.

    TL;DR If your storage system implements inline compression, performance results with small IO size random writes with time_based and runtime may be inflated with fio versions < 3.3 due to fio generating unexpectedly compressible data when using fio’s default data pattern. Although unintuitive, performance can often be increased by enabling compression especially if the bottleneck […]

    Creating compressible data with fio.

    Published: (Updated: ) in fio, , , , by gary.

    Today I used fio to create some compressible data to test on my Nutanix nodes.  I ended up using the following fio params to get what I wanted.   buffer_compress_percentage=50 refill_buffers buffer_pattern=0xdeadbeef buffer_compress_percentage does what you’d expect and specifies how compressible the data is refill_buffers Is required to make the above compress percentage do what you’d […]