15.00 - Chapter 2 AMP Load (ampload) - Teradata Database

Teradata Database Utilities

Product
Teradata Database
Release Number
15.00
Content Type
Configuration
Publication ID
B035-1102-015K
Language
English (United States)
Last Update
2018-09-25

The Amp Load utility, ampload, displays the AMP vproc usage of AMP Worker Tasks (AWTs) on Teradata Database, representing the load on each AMP vproc. The utility also displays the number of messages queued for each AMP vproc, which can demonstrate congestion on the system.

Scenarios Runs From

AMP Load runs from Database Window or comparable interface to the Teradata Database console subsystem, such as cnsterm.

For general information on starting the utilities from different interfaces, see Appendix B: “Starting the Utilities”

Scenarios Usage Notes

The following table describes the components of the ampload display.

 

Component

Description

Vproc Number

Uniquely identifies the vproc across the entire system.

Rel. Vproc#

Represents the number of the vproc number relative to the node upon which the vproc resides.

Node ID

Identifies the node cabinet number and module number upon which the vproc resides.

Msg Count

Represents the number of messages waiting (message queue length) on the AMP vproc.

AWT Availability Count

Represents the number of AMP work tasks (AWTs) available to the AMP vproc.

The AMP Load utility (ampload) and the AWT Monitor utility (awtmon) provide some similar information. The following table describes the differences between these utilities.

 

ampload

awtmon

Prints AWT INUSE count only.

Prints the AWT INUSE count by work type, that is, WORKNEW, WORKONE, and so on.

Knowing the work type for active AWTs helps to troubleshoot performance problems, specifically finding hot AMPs per node.

  • Displays only local node information when invoked from a command prompt window.
  • Prints only system-wide information when invoked from the CNS/DBW supervisor window.
  • Prints local node AWT INUSE count information by default and prints system-wide information with the [-s] option for pcl.

    Returns the data once. It does not provide a loop mode. You must manually submit the ampload command repeatedly if you wish to collect several reports for comparison.

    Provides [t [n]] options for a loop mode.

    Reports the vproc number, node ID number, message count, and AWT availability count for each vproc across the entire system.

    Provides the [-t count] option to filter the output to report only vprocs where the AWT in-use count is less than a number you specify.

    Prints a line for each vproc, even when the AWT in-use count is zero.

    Does not print a line if the AWT in-use count is zero.

    Shows how many messages are waiting on the AMP.

    Does not report the number of messages waiting on the AMP. Displays only a summary of the AWT in-use count snapshots for the local node or all nodes in the Teradata Database system.

    Scenarios Examples

    From the Database Window

    After you start ampload from the Database Window, the following appears:

    Vproc    Rel.      Node      Msg     AWT Availability
     No.     Vproc#    ID        Count        Count
    -----    ------    ------    ------- ----------------
        4         1      1-05          0         80
        0         1      1-04          0         79
        1         2      1-04          1         80
        5         2      1-05          0         80
        6         3      1-05          0         80
        2         3      1-04          1         80
        3         4      1-04          1         80
        7         4      1-05          0         80

    From the Command Line or Teradata Command Prompt

    After you start ampload from the Command Line or Teradata Command Prompt, the following appears:

    Vproc    Rel.      Node      Msg     AWT Availability
     No.     Vproc#    ID       Count         Count
    -----    ------    ------   -------  ---------------    4         1      1-05         0          80
        5         2      1-05         0          80
        6         3      1-05         0          80
        7         4      1-05         0          80