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dko
Asked: 2011-02-18 06:14:02 +0800 CST

Display IO statistics for a process

  • 772

Is there a way to view IO stats based on process in Ubuntu. I have an ubuntu server 10.10 that every once and while will grind on the hdd's for 30 seconds, I'm trying to figure out what is causing that. Thanks in advance. All I'm running on it is mysql however it happens even when mysql is not under any load (no connections just idle).

server

2 Answers

  1. Best Answer

    I use iotop (command line tool).

    sudo apt-get install iotop
    • 3

  2. iotop is doing the job most of the time. However, I found the following python script to be more useful:

    (it shows only the currently active processes)

    #!/usr/bin/python
from glob import *
from time import *
from os.path import *
import sys, os
memory = {}
sleep_time = 5;
unit = 1024.0;
unit_name = "KiB"

for argument in sys.argv:
    if argument.find( "=" ) >= 0:
        field, value = argument.split( "=" );
        if field == "s":
            sleep_time = int( value );
    if argument == "KB": #fake Kilobyte
        unit = 1000.0;
        unit_name = "KB"
    if argument == "KiB": #real Kilobyte
        unit = float(2**10)
        unit_name = "KiB"
    if argument == "MB": #fake Megabyte
        unit = 1e6;
        unit_name = "MB"
    if argument == "MiB": #real Megabyte
        unit = float(2**20)
        unit_name = "MiB"
    if argument == "GB": #fake Gigabyte
        unit = 1e9;
        unit_name = "GB"
    if argument == "GiB": #real Gigabyte
        unit = float(2**30)
        unit_name = "GiB"

while True:
    os.system( "clear" );
    table = [];
    for item in memory.items():
        item[1]["to_delete"] = 1;

    process_list = glob( "/proc/*/status" );
    for process in process_list:
        name = ""
        pid  = ""
        rb   = 0
        wb   = 0
        try:
            f = open( process, "r" );
            for line in f:
                field, value = line.split( ":" );
                if field == "Name":
                    name = value.strip();
                if field == "Pid":
                    pid = value.strip();
                    break;  
            f.close();  
            io_file = dirname( process ) + "/io"
            f = open( io_file, "r" )
            for line in f:
                field, value = line.split( ":" );
                if field == "read_bytes":
                    rb = int(value);
                if field == "write_bytes":
                    wb = int(value);
                    break;  
            f.close();              
        except:
            pass
        item = memory.get( pid, { "PID":pid, "NAME":name, "READ":rb, "WRITE":wb } );
        item["to_delete"] = 0;  
        if ( rb - item["READ"] > 0 or wb - item["WRITE"] > 0 ):
            table += [[ pid, name, rb - item["READ"], wb - item["WRITE"] ]]
        item["READ"] = rb;
        item["WRITE"] = wb;
        memory[pid] = item;
    for item in memory.items():
        if item[1]["to_delete"]:
            memory.pop( item[0] )

    print "PID".rjust(7) + "  " + "PROCESS".ljust(30)+"READ".rjust(20) + "WRITE".rjust(20)
    for row in table:
        print row[0].rjust(7) + "  " + str(row[1]).ljust(30) + ("%5.2f"%(row[2]/(sleep_time*unit)) + unit_name+"/s").rjust(20) \
                                                      + ("%5.2f"%( row[3]/(sleep_time*unit) ) + unit_name+"/s").rjust(20) 
    print "\n* ", unit_name, "=", int(unit), "Bytes"

    sleep( sleep_time );
    • 1