#!/usr/sbin/dtrace -s
/*
* fspaging.d - file system read/write and paging tracing.
* Written using DTrace (Solaris 10 3/05)
*
* This traces file related activity: system call reads and writes,
* vnode logical read and writes (fop), vnode putpage and getpage activity,
* and disk I/O. It can be used to examine the behaviour of each I/O
* layer, from the syscall interface to what the disk is doing. Behaviour
* such as read-ahead, and max I/O size breakup can be observed.
*
* This is a verbose version of fsrw.d, as this also traces paging activity.
*
* $Id: fspaging.d 3 2007-08-01 10:50:08Z brendan $
*
* USAGE: fspaging.d
*
* FIELDS:
* Event Traced event (see EVENTS below)
* Device Device, for disk I/O
* RW Either Read or Write
* Size Size of I/O in bytes, if known
* Offset Offset of I/O in kilobytes, if known
* Path Path to file on disk
*
* EVENTS:
* sc-read System call read
* sc-write System call write
* fop_read Logical read
* fop_write Logical write
* fop_getpage Logical get page
* fop_putpage Logical put page
* disk_io Physical disk I/O
* disk_ra Physical disk I/O, read ahead
*
* The events are drawn with a level of indentation, which can sometimes
* help identify related events.
*
* SEE ALSO: fsrw.d
*
* IDEA: Richard McDougall, Solaris Internals 2nd Ed, FS Chapter.
*
* COPYRIGHT: Copyright (c) 2006 Brendan Gregg.
*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at Docs/cddl1.txt
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* CDDL HEADER END
*
* ToDo: readv()
*
* 20-Mar-2006 Brendan Gregg Created this.
* 23-Apr-2006 " " Last update.
*/
#pragma D option quiet
#pragma D option switchrate=10hz
dtrace:::BEGIN
{
printf("%-13s %10s %2s %8s %6s %s\n",
"Event", "Device", "RW", "Size", "Offset", "Path");
}
syscall::*read:entry,
syscall::*write*:entry
{
/*
* starting with a file descriptior, dig out useful info
* from the corresponding file_t and vnode_t.
*/
this->filistp = curthread->t_procp->p_user.u_finfo.fi_list;
this->ufentryp = (uf_entry_t *)((uint64_t)this->filistp +
(uint64_t)arg0 * (uint64_t)sizeof (uf_entry_t));
this->filep = this->ufentryp->uf_file;
self->offset = this->filep->f_offset;
this->vnodep = this->filep != 0 ? this->filep->f_vnode : 0;
self->vpath = this->vnodep ? (this->vnodep->v_path != 0 ?
cleanpath(this->vnodep->v_path) : "<unknown>") : "<unknown>";
self->sc_trace = this->vnodep ? this->vnodep->v_type == 1 ||
this->vnodep->v_type == 2 ? 1 : 0 : 0;
}
syscall::*read:entry
/self->sc_trace/
{
printf("sc-%-10s %10s %2s %8d %6d %s\n", probefunc, ".", "R",
(int)arg2, self->offset / 1024, self->vpath);
}
syscall::*write*:entry
/self->sc_trace/
{
printf("sc-%-10s %10s %2s %8d %6d %s\n", probefunc, ".", "W",
(int)arg2, self->offset / 1024, self->vpath);
}
syscall::*read:return,
syscall::*write*:return
{
self->vpath = 0;
self->offset = 0;
self->sc_trace = 0;
}
fbt::fop_putpage:entry,
fbt::fop_getpage:entry
/self->sc_trace && args[0]->v_path/
{
printf(" %-11s %10s %2s %8d %6d %s\n", probefunc, ".",
probefunc == "fop_getpage" ? "R" : "W", (uint64_t)arg2,
args[1] / 1024, cleanpath(args[0]->v_path));
}
fbt::fop_read:entry,
fbt::fop_write:entry
/self->sc_trace && args[0]->v_path/
{
printf(" %-11s %10s %2s %8d %6d %s\n", probefunc, ".",
probefunc == "fop_read" ? "R" : "W", args[1]->uio_resid,
args[1]->_uio_offset._f / 1024, cleanpath(args[0]->v_path));
}
fbt:ufs:ufs_getpage_ra:entry
{
/* fetch the real offset (file_t is unaware of this) */
self->offset = ((inode_t *)args[0]->v_data)->i_nextrio;
self->read_ahead = 1;
}
fbt:ufs:ufs_getpage_ra:return
{
self->read_ahead = 0;
self->offset = 0;
}
io::bdev_strategy:start
{
this->offset = self->read_ahead ? self->offset : args[2]->fi_offset;
printf(" %-9s %10s %2s %8d %6d %s\n",
self->read_ahead ? "disk_ra" : "disk_io", args[1]->dev_statname,
args[0]->b_flags & B_READ ? "R" : "W", args[0]->b_bcount,
this->offset / 1024, args[2]->fi_pathname);
}