Provided by: pcp_6.0.3-1_amd64 bug

NAME

       pmiostat, pcp-iostat - report block I/O statistics

SYNOPSIS

       pcp   [pcp options]   iostat   [-u?]    [-G   method]  [-P  precision]  [-R  pattern]  [-x
       [dm][,t][,h][,noidle]]

DESCRIPTION

       pcp-iostat reports I/O statistics for SCSI (by default) or other devices (if the -x option
       is specified).

OPTIONS

       When  invoked via the pcp(1) command, the pcp options -A/--align, -a/--archive, -h/--host,
       -O/--origin,   -S/--start,   -s/--samples,   -T/--finish,   -t/--interval,   -v/--version,
       -Z/--timezone  and  -z/--hostzone  become indirectly available; refer to PCPIntro(1) for a
       complete description of these options.

       The additional command line options available for pcp-iostat are:

       -G method, --aggregate=method
            Specifies that statistics for device names matching the regular expression  specified
            with  the  -R  regex  option  should be aggregated according to method.  Note this is
            aggregation based on matching device names (not temporal aggregation).   When  -G  is
            used,  the  device  name  column  is  reported  as  method(regex), e.g.  if -G sum -R
            'sd(a|b)$'  is  specified,  the  device  column  will  be  sum(sd(a|b)$)  and  summed
            statistics  for  sda  and  sdb  will  be reported in the remaining columns.  If -G is
            specified but -R is not specified, then the default regex is .*,  i.e.  matching  all
            device  names.   If  method is sum then the statistics are summed.  This includes the
            %util column, which may therefore exceed 100% if more than one device  name  matches.
            If  method is avg then the statistics are summed and then averaged by dividing by the
            number of matching device names.  If method is min or max,  the  minimum  or  maximum
            statistics for matching devices are reported, respectively.

       -P N, --precision=N
            This  indicates  the  precision  (number  of  decimal places) to report.  The default
            precision N may be set to something other than the default (2).  Note that the avgrq-
            sz  and  avgqu-sz  fields  are always reported with N+1 decimals of precision.  These
            fields typically have values less than 1.

       -R pattern, --regex=pattern
            This restricts the report to device names matching a regular expression pattern.  The
            given  pattern  is  searched  as  a perl style regular expression, and will match any
            portion of a device name.  e.g. '^sd[a-zA-Z]+' will match all device  names  starting
            with  'sd' followed by one or more alphabetic characters.  e.g. '^sd(a|b)$' will only
            match 'sda' and 'sdb'.  e.g. 'sda$' will match 'sda' but not 'sdab'.  See also the -G
            option for aggregation options.

       -u, --no-interpolation
            When  replaying  a  set  of archives, by default values are reported according to the
            requested sample interval (-t option), not according to the actual interval  recorded
            in  the  archive(s).   Without this option PCP interpolates the values to be reported
            based on the records in the set of archives, which is particularly useful when the -t
            option  is used to replay a set of archives with a longer sampling interval than that
            with which the  archive(s)  was  originally  recorded  with.   With  the  -u  option,
            uninterpolated reporting is enabled - every value is reported according to the native
            recording interval in the set of archives.  When the -u option is specified,  the  -t
            option  makes  no sense and is incompatible because the replay interval is always the
            same as the recording interval in the set of archive.  In  addition,  -u  only  makes
            sense  when  replaying  archives,  see  the -a option on PCPIntro(1), and so if -u is
            specified then -a must also be specified.

       -V, --version
            Display version number and exit.

       -x comma-separated-options
            Specifies a comma-separated list  of  one  or  more  extended  reporting  options  as
            follows:
            dm - report statistics for device-mapper logical devices instead of SCSI devices,
            t - prefix every line in the report with a timestamp in ctime(3) format,
            h - omit the heading, which is otherwise reported every 24 samples,
            noidle - Do not display statistics for idle devices.

       -?, --help
            Display usage message and exit.

REPORT

       The columns in the pcp-iostat report have the following interpretation:

       Timestamp
              When the -x t option is specified, this column is the timestamp in ctime(3) format.

       Device Specifies the scsi device name, or if -x dm is specified, the device-mapper logical
              device name.  When -G is specified, this is replaced by the aggregation method  and
              regular expression - see the -G and -R options above.

       rrqm/s The  number of read requests expressed as a rate per-second that were merged during
              the reporting interval by the I/O scheduler.

       wrqm/s The number of write requests expressed as a rate per-second that were merged during
              the reporting interval by the I/O scheduler.

       r/s    The  number of read requests completed by the device (after merges), expressed as a
              rate per second during the reporting interval.

       w/s    The number of write requests completed by the device (after merges), expressed as a
              rate per second during the reporting interval.

       rkB/s  The  average  volume of data read from the device expressed as KBytes/second during
              the reporting interval.

       wkB/s  The average volume of data written to the device expressed as KBytes/second  during
              the reporting interval.

       avgrq-sz
              The  average  I/O request size for both reads and writes to the device expressed as
              Kbytes during the reporting interval.

       avgqu-sz
              The average queue length of read and  write  requests  to  the  device  during  the
              reporting interval.

       await  The  average  time  in  milliseconds  that read and write requests were queued (and
              serviced) to the device during the reporting interval.

       r_await
              The average time in milliseconds that read requests were queued (and  serviced)  to
              the device during the reporting interval.

       w_await
              The  average time in milliseconds that write requests were queued (and serviced) to
              the device during the reporting interval.

       %util  The percentage of time during the reporting  interval  that  the  device  was  busy
              processing requests.  A value of 100% indicates device saturation.

PCP ENVIRONMENT

       Environment variables with the prefix PCP_ are used to parameterize the file and directory
       names used by PCP.  On each installation, the file /etc/pcp.conf contains the local values
       for  these  variables.   The  $PCP_CONF  variable  may  be  used to specify an alternative
       configuration file, as described in pcp.conf(5).

       For environment variables affecting PCP tools, see pmGetOptions(3).

SEE ALSO

       PCPIntro(1), pcp(1), iostat2pcp(1),  pmcd(1),  pmchart(1),  pmlogger(1),  pcp.conf(5)  and
       pcp.env(5).