bitesize - Summarize block device I/O size as a histogram - Linux eBPF/bcc. bitesize Show I/O distribution for requested block sizes, by process name. This works by tracing block:block_rq_issue and prints a historgram of I/O size. Since this uses BPF, only the root user can use this tool. CONFIG_BPF and bcc.

Count I/O size per process until Ctrl-C is hit: # bitesize

Kbtes Size in kilobytes of range

count How many I/O fell into this range

distribution An ASCII bar chart to visualize the distribution (count column)

This traces a block I/O tracepoint to update a histogram, which is asynchronously copied to user-space. This method is very efficient, and the overhead for most storage I/O rates (< 10k IOPS) should be negligible. If you have a higher IOPS storage environment, test and quantify the overhead before use. This is from bcc. https://github.com/iovisor/bcc

Also look in the bcc distribution for a companion _examples.txt file containing example usage, output, and commentary for this tool.

Linux Unstable - in development. Allan McAleavy https://github.com/brendangregg/systemtap-lwtools/blob/master/disk/bitesize-nd.stp