Monitoring MessageQ

 

This chapter describes how to monitor the following types of MessageQ system activity on your system:

• Enable, disable, and reset statistics collection.

• View cumulative counts of the messages sent and received for all links and queues of a selected group.

  Note: For additional information about using the MessageQ Monitor utility and some of its other managing functions, see Chapter 4, "Managing MessageQ".

Enabling, Disabling, and Resetting Statistics

To monitor your application's messaging capabilities, you need to collect statistics on the queue and link activity of the groups. Because statistics collection is not automatically started when you invoke the Monitor utility, you must enable statistics-gathering from the utility.

At any time while statistics are enabled, they can be reset for a selected group's links and queues using the Reset parameter. Link and queue statistics can be reset either individually or as a whole. Using Reset zeroes out the statistics collection counters, allowing you to view your application's messaging traffic over short-term periods, which can be useful for detecting messaging bottlenecks.

Enabling Statistics From the Character-Cell Interface

To enable statistics:

1. Select Enable Statistics from the Main menu.

   The utility displays the message: Statistics enabled

Disabling Statistics From the Character-Cell Interface

To disable statistics:

1. Select Disable Statistics from the Main menu.

   The utility displays the message: Statistics disabled

Resetting Statistics From the Character-Cell Interface

To reset statistics:

1. Select one of the Reset parameters (All, Queue, Link, Single Queue, or Single Link) from the Main menu.

   The utility displays the message: Statistics reset

Enabling, Disabling, or Resetting Statistics From the Motif Interface

To enable, disable, or reset statistics:

1. Select the Manage pull-down menu.

2. Select Statistics.

3. Select Enable or Disable, or Reset.

Using the Monitor to View Link and Queue Activity

You can use the Monitor utility to view link and queue statistics of MessageQ message queuing groups.

Please note that these statistics must be enabled before they can be viewed using the Monitor utility (see the Enabling, Disabling, and Resetting Statistics topic for information about enabling statistics).

Viewing Link and Queue Activity From the Character-Cell Interface

Use the following procedure to view all linking and queuing activity from the character-cell interface:

1. Select Group Information from the Main menu.

2. Select Link or Queue from the Group Information menu.

3. Select Traffic Counts, Traffic Rates, Traffic Detail, or Link Detail to view the activity.

Viewing Link and Queue Activity From the Motif Interface

Use the following procedure to view all linking and queuing activity from the Motif interface:

1. Select the View pull-down menu.

2. Select Link Information or Queue Information.

3. Select Traffic Counts, Traffic Rates, Traffic Detail, or Detail to view the activity.

Link and Queue Activity

The descriptions and tables in this section explain the link and queue activity that can be viewed using the MessageQ Monitor utility.

You can view statistics with the following dialogs:

• Traffic Counts

• Traffic Rates

• Traffic Detail

• Detail

Viewing Link Traffic Counts

Use the Monitor utility to view the connection state and the cumulative messages and bytes for links between groups. Understand that the group for the node from which you are using the Monitor utility will not appear in this dialog; only the groups to which that group is currently connected or could be connected will appear.

Table 5-1 describes the fields of the Link Traffic Counts dialog.

Table 5-1 Link Traffic Counts Dialog

Statistic	Definition
Group Number	Number of the group
State Receiver	State of the inbound connection; either connected or unconnected
State Sender	State of the outbound connection; either connected or unconnected
Messages Sent	Cumulative messages sent form the last time statistics were reset
Messages Received	Cumulative messages received from the last time statistics were reset
Bytes Sent	Cumulative bytes sent from the last time statistics were reset
Bytes Received	Cumulative bytes received from the last time statistics were reset

This dialog can also be useful for diagnosing message flow between cross-group connections. For example, if you sent a cross-group message and it does not show up, yet the Viewing Link Traffic Counts dialog shows that all the links are up, your application may be in error.

Viewing Link Traffic Rates

Use the Link Information and Traffic Rates menu items to view the connection state and the average byte and message counts per second for the links of all groups. Average bytes and message counts per second are referred to as throughput rates. Table 5-2 describes the fields of the Link Traffic Rates dialog.

Table 5-2 Link Traffic Rates Dialog

Statistic	Definition
Group Number	Number of the group
State Receiver	State of the inbound connection; either connected or unconnected
State Sender	State of the outbound connection; either connected or unconnected
Messages Sent per Second	Average number of messages sent per second since the last time statistics were reset
Messages Received per Second	Average number of messages received per second since the last time statistics were reset
Bytes Sent per Second	Average number of bytes sent per second since the last time statistics were reset
Bytes Received per Second	Average number of bytes received per second since the last time statistics were reset

The Viewing Link Traffic Rates dialog is useful for checking the put/get rate of messages:

• If the throughput is lower than expected, the network is busier than usual (hence slower) due to other traffic.

• If the throughput is lower than expected and you suspect that enqueuing is occurring at a normal rate, but dequeuing is not happening quickly enough, the remote group's system could be congested. See the Controlling Message Flow topic in the Programmer's Guide for more information.

Viewing Link Traffic Detail

Use the Link Information and Traffic Detail menu items to view the connection state and the average byte and message counts of a single link. Table 5-3 describes the fields of the Link Traffic Detail.

Table 5-3 Link Traffic Detail Dialog

Statistic	Definition
Group Name	Name of the group
Group Number	Number of the group
State Receiver	State of the inbound connection; either connected or unconnected
State Sender	State of the outbound connection; either connected or unconnected
Messages Sent per Second	Average number of messages sent per second since the last time statistics were reset
Messages Received per Second	Average number of messages received per second since the last time statistics were reset
Bytes Sent per Second	Average number of bytes sent per second since the last time statistics were reset
Bytes Received per Second	Average number of bytes received per second since the last time statistics were reset

Use the Link Information and Traffic Detail dialog if you suspect that a traffic problem is occurring between two particular queues. If you want to narrow down the problem further and suspect that the problem is due to one queue only, use the Viewing Queue Traffic Detail dialog.

Viewing Link Detail

Use the Link Information and Detail menu items to view the link attributes of a selected group.

Table 5-4 describes the fields of the Link Detail dialog.

Table 5-4 Link Detail Dialog

Statistic	Definition
Group Name	Name of the group
Group Number	Number of the group
Time Created	First time a link was made to a remote group
Time Connected	Time the current connection to a remote group was made
Time Disconnected	Time the last connection to a remote group was severed
Time Statistics Reset	Time statistics were last reset
PID	Process ID for the sender and receiver programs
State	State of the sender and receiver programs; either connected or unconnected
Window Timer	Number of seconds the sender program must wait before using a new window. This value is set by the DELAY parameter in the %XGROUP section of the group initialization file (see the Enabling Network Connections in the Cross-Group Section topic in Chapter 3 for more information).
Window Size	Number of messages the link driver can send before it has to ask permission to send more. Window size is initially set to 0 and changes dynamically, based on the message throughput needs and the minimum and maximum values of the WINDOW parameter in the %XGROUP section of the group initialization file. For example, if a sender program sends 10 messages per second, but the receiver program can only dequeue 1 message per second, a congestion situation is created. The window size changes dynamically in a congestion situation in order to reach an equilibrium between the sender and receiver programs.
Number of Messages	Highest number of messages in the queue at any given time
Number of Bytes	Highest number of bytes in the queue at any given time
Number of Connections	Cumulative number of successful connections made by the group since it started up
Number of Connection Attempts	Number of connection attempts that failed since the last successful connection. Whenever a connection attempt is successful, this number is reset to 0.

Viewing Queue Traffic Counts

Use the Queue Information and Traffic Counts menu items to view the cumulative counts of the messages sent and received for all queues of the group. Note that statistics must be turned on for this dialog to be useful. Table 5-5 describes the fields of the Queue Traffic Counts dialog.

Table 5-5 Queue Traffic Counts Dialog

Statistic	Definition
Queue Number	Number of the queue
Messages Sent	Cumulative number of messages sent since statistics were last reset
Messages Received	Cumulative number of messages received since statistics were last reset
Messages Current	Current number of messages waiting to be read. If this value continuously increments, it could be an indication that the receiving process cannot keep up with traffic.
Bytes Sent	Cumulative size, in bytes, of messages sent since statistics were last reset
Bytes Received	Size, in bytes, of the current messages waiting to be read
Bytes Current	Size, in bytes, of the current messages waiting to be read
Queue Attributes	The type of queue, permanent or temporary. Any queue defined in the %QCT section is by default a primary queue. Queues numbered 90 to 100 and 150 to 199 are reserved exclusively for MessageQ.

Viewing Queue Traffic Rates

Use the Queue Information and Traffic Rates menu items to view the traffic rates of all queues of a particular group. Traffic rates are defined as the throughput of messages, either sent or received, per second. The Queue Traffic Rates dialog allows you to verify that suspected problems with message throughput exist.

Note that you must reset statistics each time you monitor traffic rates. Failing to do so will result in an inaccurate throughput assessment. Table 5-6 describes the fields of the Queue Traffic Rates dialog.

Table 5-6 Queue Traffic Rates Dialog

Statistic	Definition
Queue Number	Number of the queue
Messages Sent per Second	Average number of messages sent per second since statistics were last reset
Messages Received per Second	Average number of messages received per second since statistics were last reset
Bytes Sent per Second	Average number of bytes sent per second since statistics were last reset
Bytes Received per Second	Average number of bytes received per second since statistics were last reset
Peak Messages	Highest number of messages in the queue at any given time since statistics were last reset
Peak Bytes	Highest number of bytes in the queue at any given time since statistics were last reset
Queue Attributes	The type of queue, permanent or temporary. Any queue defined in the %QCT section is by default a primary queue. Queues numbered 90 to 100 and 150 to 199 are reserved exclusively for MessageQ.

Note: If you expect to see activity in the messages sent and received per second fields, but see 0.00 instead, try resetting the statistics. If an attached queue is inactive for a significant amount of time, the messages sent/received per second values approach zero because the value is derived as an average since statistics were last reset. Unless statistics are reset, these fields will not give an accurate assessment of recent queue activity.

Viewing Queue Traffic Detail

Use the Queue Information and Traffic Detail menu items to view the message and byte traffic rates of a single queue. Table 5-7 describes the fields of the Queue Traffic Detail dialog.

Table 5-7 Queue Traffic Detail Dialog

Statistic	Definition
Queue Number	Number of the queue
Messages Sent per Second	Average number of messages sent per second since statistics were last reset
Messages Received per Second	Average number of messages received per second since statistics were last reset
Bytes Sent per Second	Average number of bytes sent per second since statistics were last reset
Bytes Received per Second	Average number of bytes received per second since statistics were last reset
Peak Messages	Highest number of messages in the queue at any given time since statistics were last reset
Peak Bytes	Highest number of bytes in the queue at any given time since statistics were last reset
Queue Attributes	The type of queue, permanent or temporary. Any queue defined in the %QCT section is by default a primary queue. Queues numbered 90 to 100 and 150 to 199 are reserved exclusively for MessageQ.

Viewing Queue Detail

Use the Queue Information and Detail dialog to view the attributes of a selected queue. If quotas are enabled, they can be viewed from this dialog, Queue Information and Detail shows the last time a queue was attached and detached, which can be useful for determining whether or not your application is truly interacting with a queue.

Table 5-8 describes the fields of the Queue Detail dialog.

Table 5-8 Queue Detail Dialog

Statistic	Definition
Queue Number	Number of the queue
Queue Name	Name of the queue
Primary Queue	If the queue is secondary, the queue number of the controlling queue
Queue Attributes	The type of queue, permanent or temporary. Any queue defined in the %QCT section is by default a primary queue. Queues numbered 90 to 100 and 150 to 199 are reserved exclusively for MessageQ.
Owner PID	Process ID of the attached queue
Time Attached	Last time the queue was attached to the bus
Time Last Detached	Last time the queue was detached from the bus
Time Statistics Reset	Last time statistics for this queue were reset
Total Messages	Cumulative messages sent and received from the time statistics were last reset
Total Bytes	Cumulative bytes sent and received from the time statistics were last reset
Message Quotas	The maximum limit of uncollected messages that can reside in this queue, and the current number. This value is set by the MSG_QUOTA parameter in the %QCT section of the group initialization file.
Byte Quotas	The maximum limit of uncollected bytes that can reside in this queue, and the current number. This value is set by the BYTE_QUOTA parameter of the %QCT section in the group initialization file.