'\" t .\" Title: blk_queue_io_min .\" Author: [FIXME: author] [see http://docbook.sf.net/el/author] .\" Generator: DocBook XSL Stylesheets v1.79.1 .\" Date: March 2017 .\" Manual: Block Devices .\" Source: Kernel Hackers Manual 4.10.7 .\" Language: English .\" .TH "BLK_QUEUE_IO_MIN" "9" "March 2017" "Kernel Hackers Manual 4\&.10\&" "Block Devices" .\" ----------------------------------------------------------------- .\" * Define some portability stuff .\" ----------------------------------------------------------------- .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .\" http://bugs.debian.org/507673 .\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .ie \n(.g .ds Aq \(aq .el .ds Aq ' .\" ----------------------------------------------------------------- .\" * set default formatting .\" ----------------------------------------------------------------- .\" disable hyphenation .nh .\" disable justification (adjust text to left margin only) .ad l .\" ----------------------------------------------------------------- .\" * MAIN CONTENT STARTS HERE * .\" ----------------------------------------------------------------- .SH "NAME" blk_queue_io_min \- set minimum request size for the queue .SH "SYNOPSIS" .HP \w'void\ blk_queue_io_min('u .BI "void blk_queue_io_min(struct\ request_queue\ *\ " "q" ", unsigned\ int\ " "min" ");" .SH "ARGUMENTS" .PP \fIq\fR .RS 4 the request queue for the device .RE .PP \fImin\fR .RS 4 smallest I/O size in bytes .RE .SH "DESCRIPTION" .PP Storage devices may report a granularity or preferred minimum I/O size which is the smallest request the device can perform without incurring a performance penalty\&. For disk drives this is often the physical block size\&. For RAID arrays it is often the stripe chunk size\&. A properly aligned multiple of minimum_io_size is the preferred request size for workloads where a high number of I/O operations is desired\&. .SH "COPYRIGHT" .br