From db0871ee0e80c0f7e14069fc8911ccdbef680b50 Mon Sep 17 00:00:00 2001 From: Troels Arvin Date: Mon, 26 Jul 2010 17:05:38 +0200 Subject: [PATCH] Initial version --- plugins/other/scsi_queue | 244 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 244 insertions(+) create mode 100755 plugins/other/scsi_queue diff --git a/plugins/other/scsi_queue b/plugins/other/scsi_queue new file mode 100755 index 00000000..1a391d64 --- /dev/null +++ b/plugins/other/scsi_queue @@ -0,0 +1,244 @@ +#!/usr/bin/env python + +""" +Munin plugin which reports queue busy-values per online SCSI +device on Linux, as seen in /proc/scsi/sg/devices + +If the busy-values often reach the queue depth of the device, +one might consider increasing the queue depth. Hence, this +plugin. + +Wildcard use: +If your system has many SCSI-like devices, filtering may be needed +to make the resulting graphs readable. +If you symlink the plugin, so that it's executed as + scsi_queue_X_through_Y +then the plugin will only look at devices + /dev/sdX .. /dev/sdY +X and Y may only be one-character values. +X and Y are translated into a regular expression like: + sd[X-Y] +""" + +# Author: Troels Arvin +# See http://troels.arvin.dk/code/munin/ for latest version. + +# Only tested with Red Hat Enterprise Linux 5 / CentOS 5, currently. + +# Released according to the "New BSD License" AKA the 3-clause +# BSD License: +# ==================================================================== +# Copyright (c) 2010, Danish National Board of Health. +# All rights reserved. +# +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions are met: +# * Redistributions of source code must retain the above copyright +# notice, this list of conditions and the following disclaimer. +# * Redistributions in binary form must reproduce the above copyright +# notice, this list of conditions and the following disclaimer in the +# documentation and/or other materials provided with the distribution. +# * Neither the name of the the Danish National Board of Health nor the +# names of its contributors may be used to endorse or promote products +# derived from this software without specific prior written permission. +# +# THIS SOFTWARE IS PROVIDED BY the Danish National Board of Health ''AS IS'' AND ANY +# EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED +# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE +# DISCLAIMED. IN NO EVENT SHALL the Danish National Board of Health BE LIABLE FOR ANY +# DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES +# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; +# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND +# ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS +# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +# ==================================================================== + +# $Id: scsi_queue 13409 2010-07-26 14:58:15Z tra $ + +# Note to self: +# The fields in /proc/scsi/sg/devices are: +# host chan id lun type opens qdepth busy online + +# TODO: +# - Make it possible to group by multipath group. Might be +# hard, though, because determining path groups seems +# to require root privileges. +# - Support autoconf +# - How to support filtering on installations which have +# many SCSI devices, beyond /dev/sdz? + +import os, sys, re + +procfile = '/proc/scsi/sg/devices' +sysfs_base = '/sys/bus/scsi/devices' + +my_canonical_name = 'scsi_queue' # If called as - e.g. - scsi_queue_foo, then + # foo will be interpreted as a device filter. + # For this, we need a base name. + +def bailout(msg): + sys.stderr.write(msg+"\n") + sys.exit(1) + +def print_config(devices,filter_from,filter_through): + + title_qualification = '' + if devfilter_regex: + title_qualification = ' for devices sd%s through sd%s' % (filter_from,filter_through) + + print 'graph_title SCSI queue busy values' + title_qualification + print 'graph_vlabel busy count' + print 'graph_args --base 1000 -l 0' + print 'graph_category disk' + print 'graph_info This graph shows the queue busy values, as seen in /prod/scsi/sg/devices' + + keys = devices.keys() + keys.sort() + for key in keys: + qdepth = devices[key]['qdepth'] + print '%s.min 0' % key + print '%s.type GAUGE' % key + print '%s.label %s (%s %s); qdepth=%s' % ( + key, + key, + devices[key]['vendor'], + devices[key]['model'], + qdepth + ) + print '%s.max %s' % (key,qdepth) + +# Return a list of lists representing interesting parts from procfile +def parse_procfile(): + retval = [] + try: + fh = open(procfile) + for line in fh: + retval.append(line.split()) + + except IOError, e: + bailout('IO error: '+str(e)) + return retval + +# Try to read a file's content. If any I/O problem: return empty string +def readfile(path): + try: + f = open(path) + retval = f.read().rstrip() + f.close() + except IOError, e: + return '' + return retval + +# Return dict of dicts, indexed by device name +def map_procentries_to_devices(list_of_dicts,devfilter_regex): + device_dict={} + + if devfilter_regex: + regex_compiled = re.compile(devfilter_regex) + + for elem in list_of_dicts: + # In /sys/bus/scsi/devices we see a number of directory + # entries, such as: + # 0:0:0:0 + # 2:0:0:0 + # 3:0:0:0 + # + # The colon-separated values map to the first four parts + # of /proc/scsi/sg/devices + # And the directory entries are symlinks which point to directories + # in /sys/devices. By following a symlink, we may end up in + # a directory which contains directory entries like: + # - block:sdb + # ... + # - model + # ... + # - vendor + sys_pathname = sysfs_base + '/' + ':'.join(elem[:4]) # isolate stuff like 2:0:0:0 + + # Should actually not happen, but nontheless: + if not os.path.islink(sys_pathname): + continue + + # Search for dirent called block:SOMETHING + # Put SOMETHING into blockdev_name + # Couldn't make glob.glob() work: The length of the result + # of glob() returned TypeError: len() of unsized object on + # RHEL 5's python... + dirents = os.listdir(sys_pathname) + num_blocklines=0 + for dirent in dirents: + if dirent.startswith('block:'): + block_line = dirent + num_blocklines += 1 + if num_blocklines == 0: + continue + if num_blocklines > 1: + bailout("Got more than one result when globbing for '%s'" % glob_for) + blockdev_name = block_line.split(':')[1] + + # If device filtering is active, filter now + if devfilter_regex: + if not regex_compiled.match(blockdev_name): + continue + + # Merge info from the /proc and /sys sources + device_dict[blockdev_name] = { + 'model' : readfile(sys_pathname+'/model'), + 'vendor': readfile(sys_pathname+'/vendor'), + 'qdepth': elem[6], + 'busy' : elem[7] + } + return device_dict + +def print_values(devices): + devnames = devices.keys() + devnames.sort() + retval = '' + for devname in devnames: + print "%s.value %s" % ( + devname, + devices[devname]['busy'] + ) + + + + +# Initial sanity check +n_args=len(sys.argv) +if n_args > 2: + # At most one arg expected + print '%d arguments given - expecting only one' % n_args + sys.exit(1) + +# See if we were called with a Munin wildcard-style 'arg0-argument' +# E.g., if called as scsi_queue_a_through_c, then consider only +# devices sda, sdb, sdc. +devfilter_regex = None +called_as = os.path.basename(sys.argv[0]) +match = re.match(my_canonical_name+'_([^_])_through_([^_])', called_as) +if match: + filter_from = match.group(1) + filter_through = match.group(2) + devfilter_regex = 'sd['+filter_from+'-'+filter_through+']' + +# Perform main piece of work +devices = map_procentries_to_devices( + parse_procfile(), + devfilter_regex +) + +# See how we were called +if n_args == 2: + # An argument was given, so let's not simply print + # values. + arg = sys.argv[1] + if arg == 'config': + print_config(devices,filter_from,filter_through) + sys.exit(0) + else: + print "Unknown argument '%s'" % arg + sys.exit(1) + +# No arguments given; print values +print_values(devices)