NAME

       qslog - collects request statistics from access log data.

SYNOPSIS

       qslog -f <format_string> -o <out_file> [-p[c|u[c]] [-v]] [-x [<num>]] [-u <name>] [-m] [-c
       <path>]

DESCRIPTION

       qslog is a real time access log analyzer. It collects the data from stdin. The  output  is
       written to the specified file every minute and includes the following entries:
         - requests per second (r/s)
         - number of requests within measured time (req)
         - bytes sent to the client per second (b/s)
         - bytes received from the client per second (ib/s)
         - response status codes within the last minute (1xx,2xx,3xx,4xx,5xx)
         - average response duration (av)
         - average response duration in milliseconds (avms)
         -   distribution   of   response   durations   in   seconds   within   the  last  minute
       (<1s,1s,2s,3s,4s,5s,>5s)
         - distribution of response durations  faster  than  a  second  within  the  last  minute
       (0-49ms,50-99ms,100-499ms,500-999ms)
         - number of established (new) connections within the measured time (esco)
         - average system load (sl)
         - free memory (m) (not available for all platforms)
         - number of client ip addresses seen withn the last 600 seconds (ip)
         - number of different users seen withn the last 600 seconds (usr)
         - number of events identified by the 'E' format character
         -   number  of  mod_qos  events  within  the  last  minute  (qV=create  session,  qv=VIP
       IP,qS=session  pass,  qD=access  denied,  qK=connection  closed,  qT=dynamic   keep-alive,
       qL=request/response  slow  down,  qs=serialized request,  qA=connection abort, qU=new user
       tracking cookie)

OPTIONS

       -f <format_string>
              Defines the log data format and the positions of data elements  processed  by  this
              utility.  See to the 'LogFormat' directive of the httpd.conf file to see the format
              definitions of the servers access log data.
                   qslog knows the following elements:
                   I defines the client ip address (%h)
                   R defines the request line (%r)
                   S defines HTTP response status code (%s)
                   B defines the transferred bytes (%b or %O)
                   i defines the received bytes (%I)
                   D defines the request duration in microseconds (%D)
                   t defines the request duration in milliseconds (may be used instead of D)
                   T defines the request duration in seconds (may be used instead of D or t) (%T)
                   k defines the number of keepalive requests on the connection (%k)
                   U defines the user tracking id (%{mod_qos_user_id}e)
                   Q defines the mod_qos_ev event message (%{mod_qos_ev}e)
                   C defines the element for the detailed log (-c option), e.g. "%U"
                   s arbitrary counter to add up (sum within a minute)
                   a arbitrary counter to build an average from (average per request)
                   A arbitrary counter to build an average from (average per request)
                   M arbitrary counter to measure the maximum value reached (peak)
                   E comma separated list of event strings
                   c content type (%{content-type}o), available in -pc mode only
                   m request method (GET/POST) (%m), available in -pc mode only
                   . defines an element to ignore (unknown string)

       -o <out_file>
              Specifies the file to store the output to. stdout is used if  this  option  is  not
              defined.

       -p     Used for post processing when reading the log data from a file (cat/pipe). qslog is
              started using it's offline mode (extracting the time stamps from the log lines)  in
              order  to process existing log files. The option "-pc" may be used alternatively if
              you want to gather request information per client (identified by IP address (I)  or
              user  tracking id (U) showing how many request each client has performed within the
              captured period of time). "-pc" supports the format characters  IURSBTtDkMEcm.  The
              option  "-pu"  collects  statistics  on a per URL level (supports format characters
              RSTtD). "-puc" is very similar to "-pu" but cuts the end (handler) of each URL.

       -v     Verbose mode.

       -x [<num>]
              Rotates the output file once a day (move). You may specify the  number  of  rotated
              files to keep. Default are 14.

       -u <name>
              Becomes another user, e.g. www-data.

       -m     Calculates free system memory every minute.

       -c <path>
              Enables  the  collection  of  log  statistics  for  different request types. 'path'
              specifies the necessary rule file. Each rule consists of a rule  identifier  and  a
              regular   expression   to   identify   a  request  seprarated  by  a  colon,  e.g.,
              01:^(/a)|(/c). The regular expressions are matched against  the  log  data  element
              which has been identified by the 'C' format character.

VARIABLES

       The following environment variables are known to qslog:

       QSEVENTPATH=<path>
              Defines a file containing a comma or new line separated list of known event strings
              expected within the log filed identified by the 'E' format character.

       QSCOUNTERPATH=<path>
              Defines a file containing a by new line  separated  list  of  rules  which  reflect
              possible  QS_ClientEventLimitCount directive settings (for simulation purpose / -pc
              option). The 'E' format character defines the event string  in  the  log  to  match
              (literal string) the 'event1' and 'event2' event names against.

              Rule syntax: <name>:<event1>-<n>*<event2>/<duration>=<limit>
                   'name'  defines  the name you have given to the rule entry and is logged along
              with with the number of times the 'limit' has been reached within the 'duration'.
                   'event1' defines the variable name (if found in 'E') to increment the counter.
                   'event2' defines the variable name (if found in 'E') to decrement the  counter
              (and the parameter 'n' defines by how much).
                   'duration'   defines   the   measure   interval  (in  seconds)  used  for  the
              QS_ClientEventLimitCount directive.
                   'limit'    defines    the    threshold    (number)     defined     for     the
              QS_ClientEventLimitCount directive.

              Note:  If the 'name' parameter is prefixed by 'STATUS', the rule is applied against
              the HTTP status code 'S' and the 'event1' string shall contain a list  of  relevant
              status codes separated by an underscore (while 'event2' is ignored).

EXAMPLE

       Configuration using pipped logging:

         CustomLog  "|/usr/bin/qslog  -f  ISBDQ  -x  -o  /var/log/apache/stat.csv"  "%h %>s %b %D
       %{mod_qos_ev}e"

       Post processing:

         LogFormat "%t %h \"%r\" %>s %b \"%{User-Agent}i\" %T"
         cat access.log | qslog -f ..IRSB.T -o stat.csv -p

SEE ALSO

       qsdt(1), qsexec(1), qsfilter2(1), qsgeo(1), qsgrep(1), qshead(1),  qslogger(1),  qspng(1),
       qsre(1), qsrespeed(1), qsrotate(1), qssign(1), qstail(1)

AUTHOR

       Pascal Buchbinder, http://mod-qos.sourceforge.net/