/usr/share/systemtap/examples/io
Edit: /usr/share/systemtap/examples/io/disktop.stp (1794B)
#!/usr/bin/stap
#
# Copyright (C) 2007 Oracle Corp.
#
# Get the status of reading/writing disk every 5 seconds,
# output top ten entries
#
# This is free software,GNU General Public License (GPL);
# either version 2, or (at your option) any later version.
#
# Usage:
# ./disktop.stp
#
global io_stat,device
global read_bytes,write_bytes
probe vfs.read.return {
if (returnval()>0) {
if (devname!="N/A") {/*skip read from cache*/
io_stat[pid(),execname(),uid(),ppid(),"R"] += returnval()
device[pid(),execname(),uid(),ppid(),"R"] = devname
read_bytes += returnval()
}
}
}
probe vfs.write.return {
if (returnval()>0) {
if (devname!="N/A") { /*skip update cache*/
io_stat[pid(),execname(),uid(),ppid(),"W"] += returnval()
device[pid(),execname(),uid(),ppid(),"W"] = devname
write_bytes += returnval()
}
}
}
probe timer.ms(5000) {
/* skip non-read/write disk */
if (read_bytes+write_bytes) {
printf("\n%-25s, %-8s%4dKb/sec, %-7s%6dKb, %-7s%6dKb\n\n",
ctime(gettimeofday_s()),
"Average:", ((read_bytes+write_bytes)/1024)/5,
"Read:",read_bytes/1024,
"Write:",write_bytes/1024)
/* print header */
printf("%8s %8s %8s %25s %8s %4s %12s\n",
"UID","PID","PPID","CMD","DEVICE","T","BYTES")
}
/* print top ten I/O */
foreach ([process,cmd,userid,parent,action] in io_stat- limit 10)
printf("%8d %8d %8d %25s %8s %4s %12d\n",
userid,process,parent,cmd,
device[process,cmd,userid,parent,action],
action,io_stat[process,cmd,userid,parent,action])
/* clear data */
delete io_stat
delete device
read_bytes = 0
write_bytes = 0
}
probe end{
delete io_stat
delete device
delete read_bytes
delete write_bytes
}