Optional Color Support

    https://metacpan.org/module/Term::ANSIColor

Once you do, pgtop will automatically use it. However, color is not yet working on Windows. Patches welcome. :-)

Optional Hi-Res Timing

Platforms

  * Linux (2.2.x, 2.4.x) ?
  * FreeBSD (2.2, 3.x, 4.x) ?
  * Mac OS X ?
  * BSDI 4.x ?
  * Solaris 2.x ?
  * Windows NT 4.x (ActivePerl) ?

If you find that it works on another platform, please let us know. Given that it is all Perl code, I expect it to be rather portable to Unix and Unix-like systems. Heck, it might even work on Win32 systems.

The Basics

pgtop will connect to a PostgreSQL server and periodically run queries against the pg_stat* relations and attempt to summarize the information from them in a useful format.

WHAT FOLLOWS REFERS TO MYTOP

The Display

MySQL on localhost (4.0.13-log) up 1+11:13:00 [23:29:11] Queries: 19.3M qps: 160 Slow: 1.0 Se/In/Up/De(%): 00/80/03/17 qps now: 219 Slow qps: 0.0 Threads: 1 ( 1/ 16) 00/74/00/25 Key Efficiency: 99.3% Bps in/out: 30.5k/162.8 Now in/out: 32.7k/ 3.3k

The first line identifies the hostname of the server (localhost) and the version of MySQL it is running. The right had side shows the uptime of the MySQL server process in days+hours:minutes:seconds format (much like FreeBSD's top) as well as the current time.

The second line displays the total number of queries the server has processed, the average number of queries per second, the number of slow queries, and the percentage of Select, Insert, Update, and Delete queries.

The third real-time values. First is the number of queries per second, then the number of slow queries, followed by query precentages (like on the previous line).

And the fourth line displays key buffer efficiency (how often keys are read from the buffer rather than disk) and the number of bytes that MySQL has sent and received, both over all and in the last cycle.

You can toggle the header by hitting h when running mytop.

The second part of the display lists as many threads as can fit on screen. By default they are sorted according to their idle time (least idle first). The display looks like:

    Id     User       Host      Dbase   Time      Cmd Query or State
    --     ----       ----      -----   ----      --- --------------
    61  jzawodn  localhost      music      0    Query show processlist

As you can see, the thread id, username, host from which the user is connecting, database to which the user is connected, number of seconds of idle time, the command the thread is executing, and the query info are all displayed.

Often times the query info is what you are really interested in, so it is good to run mytop in an xterm that is wider than the normal 80 columns if possible.

The thread display color-codes the threads if you have installed color support. The current color scheme only works well in a window with a dark (like black) background. The colors are selected according to the "Command" column of the display:

    Query   -  Yellow
    Sleep   -  White
    Connect -  Green

Those are purely arbitrary and will be customizable in a future release. If they annoy you just start mytop with the -nocolor flag or adjust your config file appropriately.

Arguments

-u or -user username

Username to use when logging in to the MySQL server. Default: ``root''.

-p or -pass or -password password

Password to use when logging in to the MySQL server. Default: none.

-h or -host hostname[:port]

Hostname of the MySQL server. The hostname may be followed by an option port number. Note that the port is specified separate from the host when using a config file. Default: ``localhost''.

-port or -P port

If you're running MySQL on a non-standard port, use this to specify the port number. Default: 3306.

-s or -delay seconds

How long between display refreshes. Default: 5

-d or -db or -database database

Use if you'd like mytop to connect to a specific database by default. Default: ``test''.

-b or -batch or -batchmode

In batch mode, mytop runs only once, does not clear the screen, and places no limit on the number of lines it will print. This is suitable for running periodically (perhaps from cron) to capture the information into a file for later viewing. You might use batch mode in a CGI script to occasionally display your MySQL server status on the web.

Default: unset.

-S or -socket /path/to/socket

If you're running mytop on the same host as MySQL, you may wish to have it use the MySQL socket directly rather than a standard TCP/IP connection. If you do,just specify one.

Note that specifying a socket will make mytop ignore any host and/or port that you might have specified. If the socket does not exist (or the file specified is not a socket), this option will be ignored and mytop will use the hostname and port number instead.

Default: none.

-header or -noheader

Sepcify if you want the header to display or not. You can toggle this with the h key while mytop is running.

Default: header.

-color or -nocolor

Specify if you want a color display. This has no effect if you don't have color support available.

Default: If you have color support, mytop will try color unless you tell it not to.

-i or -idle or -noidle

Specify if you want idle (sleeping) threads to appear in the list. If sleeping threads are omitted, the default sorting order is reversed so that the longest running queries appear at the top of the list.

Default: idle.

-prompt or -noprompt

Specify if you want to be prompted to type in your database password. This provides a little bit more security since it not only prevents the password from viewable in a process list, but also doesn't require the password to be stored in plain text in your ~/.mytop config file. You will only be prompted if a password has not been specified in your config file or through another command line option.

Default: noprompt.

-resolve

If you have skip-resolve set on MySQL (to keep it from doing a reverse DNS lookup on each inbound connection), mytop can replace IP addresses with hostnames but toggling this option.

Default: noresolve

-slow_threshold

Defines the threshold in seconds after which a query must be considered slow and it's logged to a file (`pgtop.log`).

Default: 60

-slack_webhook

If provided, in the form of a slack incoming webhook URL (e.g. <https://hooks.slack.com/services/...>), it will be used to send notifications for queries that are running longer than "slow_threshold" seconds.

There is no default value, so no slack notification will be sent if this parameter is not provided.

Default: none

Command-line arguments will always take precedence over config file options. That happens because the config file is read BEFORE the command-line arguments are applied.

Config File

Here is a sample config file "~/.pgtop" which implements the defaults described above.

  user=root
  pass=
  host=localhost
  db=test
  delay=5
  port=3306
  batchmode=0
  header=1
  color=1
  idle=1

Using a config file will help to ensure that your database password isn't visible to users on the command-line. Just make sure that the permissions on "~/.pgtop" are such that others cannot read it (unless you want them to, of course).

You may have white space on either side of the "=" in lines of the config file.

Shortcut Keys

?

Display help.

c

Show "command counters" based on the Com_* values in SHOW STATUS. This is a new feature. Feedback welcome.

d

Show only threads connected to a particular database.

f

Given a thread id, display the entire query that thread was (and still may be) running.

F

Disable all filtering (host, user, and db).

h

Only show queries from a particular host.

H

Toggle the header display. You can also specify either "header=0" or "header=1" in your config file to set the default behavior.

i

Toggle the display of idle (sleeping) threads. If sleeping threads are filtered, the default sorting order is reversed so that the longest running queries appear at the top of the list.

k

Kill a thread.

K

Kill all threads/queries that have been running for longer than a given threshold in seconds.

m

Toggle modes. Currently this switches from `top' mode to `qps' (Queries Per Second Mode). In this mode, mytop will write out one integer per second. The number written reflects the number of queries executed by the server in the previous one second interval.

More modes may be added in the future.

o

Reverse the default sort order.

p

Pause display.

q

Quit pgtop

r

Reset the server's status counters via a FLUSH STATUS command.

s

Change the sleep time (number of seconds between display refreshes).

u

Show only threads owned by a giver user.

The s key has a command-line counterpart: -s.

The h key has two command-line counterparts: -header and -noheader.