1 The following are demonstrations of the vopstat script.
4 By default, vopstat traces activity at the vnode interface and prints
5 summaries every five seconds. It will either trace all filesystems or
6 just the mountpoint specified.
8 Here it was run on /extra1, while a tar command archived /extra1,
30 VOP Wall Time mSeconds
47 There were 66 calls for physical I/O operations, fop_getpage, as files
48 were read from disk. The VOP Count show that there were many calls to
49 fop_putpage and fop_getpage, as tar works its way through files; and
50 many more to fop_dispose. The total elaspsed time for these calls
51 are listed at the bottom, in milleseconds.
53 This rate of events will put some pressure on the DTrace buffer,
54 you may see dynamic variable drops.
58 vopstat also has a -t option to trace activity. Here it is run on /extra1
59 while an "ls" command listed files from that directory,
61 # ./vopstat -t /extra1
62 Event Device Path RW Size Offset
63 -> fop_getattr - /extra1 - 0 0
64 <- fop_getattr - /extra1 - 0 0
65 -> fop_access - /extra1 - 0 0
66 <- fop_access - /extra1 - 0 0
67 -> fop_open - /extra1 - 0 0
68 <- fop_open - /extra1 - 0 0
69 -> fop_getattr - /extra1 - 0 0
70 <- fop_getattr - /extra1 - 0 0
71 -> fop_rwlock - /extra1 - 0 0
72 <- fop_rwlock - /extra1 - 0 0
73 -> fop_readdir - /extra1 - 0 0
74 -> fop_getpage - /extra1 - 0 0
75 <- fop_getpage - /extra1 - 0 0
76 -> fop_rwunlock - /extra1 - 0 0
77 <- fop_rwunlock - /extra1 - 0 0
78 -> fop_rwlock - /extra1 - 0 0
79 <- fop_rwlock - /extra1 - 0 0
80 -> fop_readdir - /extra1 - 0 0
81 <- fop_readdir - /extra1 - 0 0
82 -> fop_rwunlock - /extra1 - 0 0
83 <- fop_rwunlock - /extra1 - 0 0
84 -> fop_close - /extra1 - 0 512
85 <- fop_close - /extra1 - 0 512
88 Each call can be seen as it happened, including the entry and return of