1 #!/usr/sbin/dtrace -s 2 /* 3 * fspaging.d - file system read/write and paging tracing. 4 * Written using DTrace (Solaris 10 3/05) 5 * 6 * This traces file related activity: system call reads and writes, 7 * vnode logical read and writes (fop), vnode putpage and getpage activity, 8 * and disk I/O. It can be used to examine the behaviour of each I/O 9 * layer, from the syscall interface to what the disk is doing. Behaviour 10 * such as read-ahead, and max I/O size breakup can be observed. 11 * 12 * This is a verbose version of fsrw.d, as this also traces paging activity. 13 * 14 * $Id: fspaging.d,v 1.1.1.1 2015/09/30 22:01:09 christos Exp $ 15 * 16 * USAGE: fspaging.d 17 * 18 * FIELDS: 19 * Event Traced event (see EVENTS below) 20 * Device Device, for disk I/O 21 * RW Either Read or Write 22 * Size Size of I/O in bytes, if known 23 * Offset Offset of I/O in kilobytes, if known 24 * Path Path to file on disk 25 * 26 * EVENTS: 27 * sc-read System call read 28 * sc-write System call write 29 * fop_read Logical read 30 * fop_write Logical write 31 * fop_getpage Logical get page 32 * fop_putpage Logical put page 33 * disk_io Physical disk I/O 34 * disk_ra Physical disk I/O, read ahead 35 * 36 * The events are drawn with a level of indentation, which can sometimes 37 * help identify related events. 38 * 39 * SEE ALSO: fsrw.d 40 * 41 * IDEA: Richard McDougall, Solaris Internals 2nd Ed, FS Chapter. 42 * 43 * COPYRIGHT: Copyright (c) 2006 Brendan Gregg. 44 * 45 * CDDL HEADER START 46 * 47 * The contents of this file are subject to the terms of the 48 * Common Development and Distribution License, Version 1.0 only 49 * (the "License"). You may not use this file except in compliance 50 * with the License. 51 * 52 * You can obtain a copy of the license at Docs/cddl1.txt 53 * or http://www.opensolaris.org/os/licensing. 54 * See the License for the specific language governing permissions 55 * and limitations under the License. 56 * 57 * CDDL HEADER END 58 * 59 * ToDo: readv() 60 * 61 * 20-Mar-2006 Brendan Gregg Created this. 62 * 23-Apr-2006 " " Last update. 63 */ 64 65 #pragma D option quiet 66 #pragma D option switchrate=10hz 67 68 dtrace:::BEGIN 69 { 70 printf("%-13s %10s %2s %8s %6s %s\n", 71 "Event", "Device", "RW", "Size", "Offset", "Path"); 72 } 73 74 syscall::*read:entry, 75 syscall::*write*:entry 76 { 77 /* 78 * starting with a file descriptior, dig out useful info 79 * from the corresponding file_t and vnode_t. 80 */ 81 this->filistp = curthread->t_procp->p_user.u_finfo.fi_list; 82 this->ufentryp = (uf_entry_t *)((uint64_t)this->filistp + 83 (uint64_t)arg0 * (uint64_t)sizeof (uf_entry_t)); 84 this->filep = this->ufentryp->uf_file; 85 self->offset = this->filep->f_offset; 86 this->vnodep = this->filep != 0 ? this->filep->f_vnode : 0; 87 self->vpath = this->vnodep ? (this->vnodep->v_path != 0 ? 88 cleanpath(this->vnodep->v_path) : "<unknown>") : "<unknown>"; 89 self->sc_trace = this->vnodep ? this->vnodep->v_type == 1 || 90 this->vnodep->v_type == 2 ? 1 : 0 : 0; 91 } 92 93 syscall::*read:entry 94 /self->sc_trace/ 95 { 96 printf("sc-%-10s %10s %2s %8d %6d %s\n", probefunc, ".", "R", 97 (int)arg2, self->offset / 1024, self->vpath); 98 } 99 100 syscall::*write*:entry 101 /self->sc_trace/ 102 { 103 printf("sc-%-10s %10s %2s %8d %6d %s\n", probefunc, ".", "W", 104 (int)arg2, self->offset / 1024, self->vpath); 105 } 106 107 syscall::*read:return, 108 syscall::*write*:return 109 { 110 self->vpath = 0; 111 self->offset = 0; 112 self->sc_trace = 0; 113 } 114 115 fbt::fop_putpage:entry, 116 fbt::fop_getpage:entry 117 /self->sc_trace && args[0]->v_path/ 118 { 119 printf(" %-11s %10s %2s %8d %6d %s\n", probefunc, ".", 120 probefunc == "fop_getpage" ? "R" : "W", (uint64_t)arg2, 121 args[1] / 1024, cleanpath(args[0]->v_path)); 122 } 123 124 125 fbt::fop_read:entry, 126 fbt::fop_write:entry 127 /self->sc_trace && args[0]->v_path/ 128 { 129 printf(" %-11s %10s %2s %8d %6d %s\n", probefunc, ".", 130 probefunc == "fop_read" ? "R" : "W", args[1]->uio_resid, 131 args[1]->_uio_offset._f / 1024, cleanpath(args[0]->v_path)); 132 } 133 134 fbt:ufs:ufs_getpage_ra:entry 135 { 136 /* fetch the real offset (file_t is unaware of this) */ 137 self->offset = ((inode_t *)args[0]->v_data)->i_nextrio; 138 self->read_ahead = 1; 139 } 140 141 fbt:ufs:ufs_getpage_ra:return 142 { 143 self->read_ahead = 0; 144 self->offset = 0; 145 } 146 147 io::bdev_strategy:start 148 { 149 this->offset = self->read_ahead ? self->offset : args[2]->fi_offset; 150 printf(" %-9s %10s %2s %8d %6d %s\n", 151 self->read_ahead ? "disk_ra" : "disk_io", args[1]->dev_statname, 152 args[0]->b_flags & B_READ ? "R" : "W", args[0]->b_bcount, 153 this->offset / 1024, args[2]->fi_pathname); 154 } 155