pt-heartbeat

# pt-heartbeat --update -h 192.168.244.10 -u monitor -p monitor123 -D test

# pt-heartbeat --update -h 192.168.244.10 -u monitor -p monitor123 --database test 
# pt-heartbeat --update -h 192.168.244.10 -u monitor -p monitor123 --database=test 

10061.00s [ 167.68s, 33.54s, 11.18s ]
10062.00s [ 335.38s, 67.08s, 22.36s ]
10063.01s [ 503.10s, 100.62s, 33.54s ]
...

10039.00

Prompt for a password when connecting to MySQL.

short form: -A; type: string
Default character set. If the value is utf8, sets Perl’s binmode on STDOUT to utf8, passes the mysql_enable_utf8 option to DBD::mysql, and runs SET NAMES UTF8 after connecting to MySQL. Any other value sets binmode
on STDOUT without the utf8 layer, and runs SET NAMES after connecting to MySQL.

Check slave delay once and exit. If you also specify --recurse, the tool will try to discover slave’s of the given slave and check and print their lag, too. The hostname or IP and port for each slave is printed before its
delay. --recurse only works with MySQL.

Check if the server has read_only enabled; If it does, the tool skips doing any inserts.

option
option=value

# cat pt-heartbeat.conf 
host=192.168.244.20
user=monitor
password=monitor123
monitor
database=test
master-server-id=1 

CREATE TABLE heartbeat (
ts varchar(26) NOT NULL,
server_id int unsigned NOT NULL PRIMARY KEY,
file varchar(255) DEFAULT NULL, -- SHOW MASTER STATUS
position bigint unsigned DEFAULT NULL, -- SHOW MASTER STATUS
relay_master_log_file varchar(255) DEFAULT NULL, -- SHOW SLAVE STATUS
exec_master_log_pos bigint unsigned DEFAULT NULL -- SHOW SLAVE STATUS
);

Create the heartbeat --table if it does not exist.
This option causes the table specified by --database and --table to be created with the following MAGIC_create_heartbeat table definition:
CREATE TABLE heartbeat (
ts varchar(26) NOT NULL,
server_id int unsigned NOT NULL PRIMARY KEY,
file varchar(255) DEFAULT NULL, -- SHOW MASTER STATUS
position bigint unsigned DEFAULT NULL, -- SHOW MASTER STATUS
relay_master_log_file varchar(255) DEFAULT NULL, -- SHOW SLAVE STATUS
exec_master_log_pos bigint unsigned DEFAULT NULL -- SHOW SLAVE STATUS
);
The heartbeat table requires at least one row. If you manually create the heartbeat table, then you must insert a row by doing:
INSERT INTO heartbeat (ts, server_id) VALUES (NOW(), N);
or if using --utc:
INSERT INTO heartbeat (ts, server_id) VALUES (UTC_TIMESTAMP(), N);
where N is the server’s ID; do not use @@server_id because it will replicate and slaves will insert their own server ID instead of the master’s server ID.
This is done automatically by --create-table.
A legacy version of the heartbeat table is still supported:
CREATE TABLE heartbeat (
id int NOT NULL PRIMARY KEY,
ts datetime NOT NULL
);
Legacy tables do not support --update instances on each slave of a multi-slave hierarchy like “master ->slave1 -> slave2”. To manually insert the one required row into a legacy table:
INSERT INTO heartbeat (id, ts) VALUES (1, NOW());
or if using --utc:
INSERT INTO heartbeat (id, ts) VALUES (1, UTC_TIMESTAMP());
The tool automatically detects if the heartbeat table is legacy.

type: string
Sets the engine to be used for the heartbeat table. The default storage engine is InnoDB as of MySQL 5.5.5.

Fork to the background and detach from the shell. POSIX operating systems only.

short form: -D; type: string
The database to use for the connection.

default: mysql; type: string
Specify a driver for the connection; mysql and Pg are supported.

short form: -F; type: string
Only read mysql options from the given file. You must give an absolute pathname.

# cat result 
1376.00s [ 1126.25s, 225.25s, 75.08s ]

type: string
Print latest --monitor output to this file.
When --monitor is given, prints output to the specified file instead of to STDOUT. The file is opened, truncated,and closed every interval, so it will only contain the most recent statistics. Useful when --daemonize
is given.

type: string; default: 1m,5m,15m
Timeframes for averages.
Specifies the timeframes over which to calculate moving averages when --monitor is given. Specify as a comma-separated list of numbers with suffixes. The suffix can be s for seconds, m for minutes, h for hours, or d
for days. The size of the largest frame determines the maximum memory usage, as up to the specified number of per-second samples are kept in memory to calculate the averages. You can specify as many timeframes as
you like.

Show help and exit.

short form: -h; type: string
Connect to host.

default: yes
Insert a heartbeat row in the --table if one doesn’t exist.
The heartbeat --table requires a heartbeat row, else there’s nothing to --update, --monitor, or --check! By default, the tool will insert a heartbeat row if one is not already present. You can disable this
feature by specifying --no-insert-heartbeat-row in case the database user does not have INSERT privileges.

# pt-heartbeat -D test --update -h 192.168.244.10 -u monitor -p monitor123 --no-insert-heartbeat-row
No row found in heartbeat table for server_id 1.
At least one row must be inserted into the heartbeat table for server_id 1.
Please read the DESCRIPTION section of the pt-heartbeat POD.

default: yes
Insert a heartbeat row in the --table if one doesn’t exist.
The heartbeat --table requires a heartbeat row, else there’s nothing to --update, --monitor, or --check! By default, the tool will insert a heartbeat row if one is not already present. You can disable this
feature by specifying --no-insert-heartbeat-row in case the database user does not have INSERT privileges.

type: float; default: 1.0
How often to update or check the heartbeat --table. Updates and checks begin on the first whole second then repeat every --interval seconds for --update and every --interval plus --skew seconds for
--monitor.
For example, if at 00:00.4 an --update instance is started at 0.5 second intervals, the first update happens at 00:01.0, the next at 00:01.5, etc. If at 00:10.7 a --monitor instance is started at 0.05 second intervals with
the default 0.5 second --skew, then the first check happens at 00:11.5 (00:11.0 + 0.5) which will be --skew seconds after the last update which, because the instances are checking at synchronized intervals, happened at
00:11.0.
The tool waits for and begins on the first whole second just to make the interval calculations simpler. Therefore,the tool could wait up to 1 second before updating or checking.
The minimum (fastest) interval is 0.01, and the maximum precision is two decimal places, so 0.015 will be rounded to 0.02.
If a legacy heartbeat table (see --create-table) is used, then the maximum precision is 1s because the ts column is type datetime.

type: string
Print all output to this file when daemonized.

The --master-server-id option must be specified because the heartbeat table `test`.`heartbeat` uses the server_id column for --update or --check but the server‘s master could not be automatically determined.

type: string
Calculate delay from this master server ID for --monitor or --check. If not given, pt-heartbeat attempts to connect to the server’s master and determine its server id.

Monitor slave delay continuously.
Specifies that pt-heartbeat should check the slave’s delay every second and report to STDOUT (or if --file is given, to the file instead). The output is the current delay followed by moving averages over the timeframe
given in --frames. For example,
5s [ 0.25s, 0.05s, 0.02s ]

short form: -p; type: string
Password to use when connecting. If password contains commas they must be escaped with a backslash:
“exam,ple”

type: string
Create the given PID file. The tool won’t start if the PID file already exists and the PID it contains is different than the current PID. However, if the PID file exists and the PID it contains is no longer running, the tool will
overwrite the PID file with the current PID. The PID file is removed automatically when the tool exits.

short form: -P; type: int
Port number to use for connection.

1272.00s [ 21.20s,  4.24s,  1.41s ]

1272.00s [ 21.20s,  4.24s,  1.41s ] 1

Print the auto-detected or given --master-server-id. If --check or --monitor is specified, specifying this option will print the auto-detected or given --master-server-id at the end of each line.

type: int
Check slaves recursively to this depth in --check mode.
Try to discover slave servers recursively, to the specified depth. After discovering servers, run the check on each one of them and print the hostname (if possible), followed by the slave delay.
This currently works only with MySQL. See --recursion-method.

type: array; default: processlist,hosts
Preferred recursion method used to find slaves.
Possible methods are:
METHOD USES
=========== ==================
processlist SHOW PROCESSLIST
hosts SHOW SLAVE HOSTS
none Do not find slaves
The processlist method is preferred because SHOW SLAVE HOSTS is not reliable. However, the hosts method is required if the server uses a non-standard port (not 3306). Usually pt-heartbeat does the right thing and finds
the slaves, but you may give a preferred method and it will be used first. If it doesn’t find any slaves, the other methods will be tried.

Use REPLACE instead of UPDATE for –update.
When running in --update mode, use REPLACE instead of UPDATE to set the heartbeat table’s timestamp.The REPLACE statement is a MySQL extension to SQL. This option is useful when you don’t know whether
the table contains any rows or not. It must be used in conjunction with –update.

type: time
Time to run before exiting.

type: string; default: /tmp/pt-heartbeat-sentinel
Exit if this file exists.

type: string
Sets the user to be used to connect to the slaves. This parameter allows you to have a different user with less privileges on the slaves but that user must exist on all slaves.

type: string
Sets the password to be used to connect to the slaves. It can be used with –slave-user and the password for the user must be the same on all slaves.

type: Array
Set the MySQL variables in this comma-separated list of variable=value pairs.
By default, the tool sets:
wait_timeout=10000
Variables specified on the command line override these defaults. For example, specifying --set-vars wait_timeout=500 overrides the defaultvalue of 10000.
The tool prints a warning and continues if a variable cannot be set.

         my ($ts, $hostname, $server_id) = $sth->fetchrow_array();
         my $now = time;
         PTDEBUG && _d("Heartbeat from server", $server_id, "\n",
            " now:", ts($now, $utc), "\n",
            "  ts:", $ts, "\n",
            "skew:", $skew);
         my $delay = $now - unix_timestamp($ts, $utc) - $skew;
         PTDEBUG && _d(‘Delay‘, sprintf(‘%.6f‘, $delay), ‘on‘, $hostname);

         # Because we adjust for skew, if the ts are less than skew seconds
         # apart (i.e. replication is very fast) then delay will be negative. 
         # So it‘s effectively 0 seconds of lag.
         $delay = 0.00 if $delay < 0;

type: float; default: 0.5
How long to delay checks.
The default is to delay checks one half second. Since the update happens as soon as possible after the beginning of the second on the master, this allows one half second of replication delay before reporting that the slave lags
the master by one second. If your clocks are not completely accurate or there is some other reason you’d like to delay the slave more or less, you can tweak this value. Try setting the PTDEBUG environment variable to see
the effect this has.

short form: -S; type: string
Socket file to use for connection.

type: string; default: heartbeat
The table to use for the heartbeat.
Don’t specify database.table; use --database to specify the database.
See --create-table.

Update a master’s heartbeat.

short form: -u; type: string
User for login if not current user.

Ignore system time zones and use only UTC. By default pt-heartbeat does not check or adjust for different system or MySQL time zones which can cause the tool to compute the lag incorrectly. Specifying this option is
a good idea because it ensures that the tool works correctly regardless of time zones.
If used, this option must be used for all pt-heartbeat instances: --update, --monitor, --check, etc.
You should probably set the option in a --config file. Mixing this option with pt-heartbeat instances not using this option will cause false-positive lag readings due to different time zones (unless all your systems are
set to use UTC, in which case this option isn’t required).

Check for the latest version of Percona Toolkit, MySQL, and other programs.
84 Chapter 2. Tools
Percona Toolkit Documentation, Release 2.2.19
This is a standard “check for updates automatically” feature, with two additional features. First, the tool checks the version of other programs on the local system in addition to its own version. For example, it checks the
version of every MySQL server it connects to, Perl, and the Perl module DBD::mysql. Second, it checks for and warns about versions with known problems. For example, MySQL 5.5.25 had a critical bug and was re-released
as 5.5.25a.
Any updates or known problems are printed to STDOUT before the tool’s normal output. This feature should never interfere with the normal operation of the tool.