Micron Confidential Hi Karim, You should be fine using the flow setting. I typically use flow for approximate distributions and rate+AF8-iops for specifying the exact number of I/O operations I want to generate per job. Micron Confidential -----Original Message----- From: Karim Manaouil +ADw-kmanaouil.dev+AEA-gmail.com+AD4- Sent: Thursday, February 27, 2025 4:29 AM To: fio+AEA-vger.kernel.org Cc: kmanaouil.dev+AEA-gmail.com Subject: +AFs-EXT+AF0- A question about fio flows CAUTION: EXTERNAL EMAIL. Do not click links or open attachments unless you recognize the sender and were expecting this message. Hi all, I am working on some experiments where I need to have 12 jobs. Each job is reading from a different file (job1 -+AD4- file1, job2 -+AD4- file2, etc). Now, some files should receieve more I/O than others. To implement this bias between files, I opted for flows. Basically, I start from 100 and I assign a percentage to each file. For example, a snippet of my fio job file below: +AFs-private-0+AF0- flow+AD0-37 filename+AD0-/srv/dax/private/private-0 +AFs-private-1+AF0- flow+AD0-23 filename+AD0-/srv/dax/private/private-1 +AFs-private-2+AF0- flow+AD0-10 filename+AD0-/srv/dax/private/private-2 +AFs-private-3+AF0- flow+AD0-9 filename+AD0-/srv/dax/private/private-3 +AFs-private-4+AF0- flow+AD0-7 filename+AD0-/srv/dax/private/private-4 +AFs-private-5+AF0- flow+AD0-3 filename+AD0-/srv/dax/private/private-5 +AFs-private-6+AF0- flow+AD0-3 filename+AD0-/srv/dax/private/private-6 I am not sure if this is properly achieving what I want to achieve. I have a doubt that having too many files and many flows will reduce scheduling precision or introduce scheduling overhead. I don't know how this feature is implemented internally, thus my question. Can you please briefly explain how the feature works. And Do you think this is a sane approach? If not, what better alternative can I use? -- Best, Karim Edinburgh University
