probe::ioblock.request(3stap) centos man page | unix.com

PROBE::IOBLOCK.REQ(3stap)				  IO Scheduler and block IO Taps				 PROBE::IOBLOCK.REQ(3stap)

NAME
       probe::ioblock.request - Fires whenever making a generic block I/O request.

SYNOPSIS
       ioblock.request

VALUES
       None

DESCRIPTION
       name - name of the probe point devname - block device name ino - i-node number of the mapped file sector - beginning sector for the entire
       bio flags - see below BIO_UPTODATE 0 ok after I/O completion BIO_RW_BLOCK 1 RW_AHEAD set, and read/write would block BIO_EOF 2
       out-out-bounds error BIO_SEG_VALID 3 nr_hw_seg valid BIO_CLONED 4 doesn't own data BIO_BOUNCED 5 bio is a bounce bio BIO_USER_MAPPED 6
       contains user pages BIO_EOPNOTSUPP 7 not supported

       rw - binary trace for read/write request vcnt - bio vector count which represents number of array element (page, offset, length) which make
       up this I/O request idx - offset into the bio vector array phys_segments - number of segments in this bio after physical address coalescing
       is performed hw_segments - number of segments after physical and DMA remapping hardware coalescing is performed size - total size in bytes
       bdev - target block device bdev_contains - points to the device object which contains the partition (when bio structure represents a
       partition) p_start_sect - points to the start sector of the partition structure of the device

CONTEXT
       The process makes block I/O request

SystemTap Tapset Reference					     June 2014						 PROBE::IOBLOCK.REQ(3stap)