Books
in black and white
Main menu
Share a book About us Home
Books
Biology Business Chemistry Computers Culture Economics Fiction Games Guide History Management Mathematical Medicine Mental Fitnes Physics Psychology Scince Sport Technics
Ads

Teradata RDBMS Database Administration - NCR

NCR Teradata RDBMS Database Administration - NCR , 2004. - 616 p.
Download (direct link): teradatadatabaseadmin2004.pdf
Previous << 1 .. 188 189 190 191 192 193 < 194 > 195 196 197 198 199 200 .. 218 >> Next

Update a large number of rows in a large table MultiLoad BTEQ insert table into a new one.
Delete a small number of rows from any table TPump BTEQ
Delete a large number of rows from a large table MultiLoad BTEQ remaining rows without a new table.
Delete all rows from any table BTEQ
Perform multiple DML (INSERT, UPDATE, DELETE) operations on a small number of rows on multiple tables MultiLoad or TPump when the transaction density is too low for satisfactory performance BTEQ
Perform multiple DML (INSERT, UPDATE, DELETE) operations on a large number of rows on multiple tables MultiLoad TPump
Copy one or several tables to a different Teradata RDBMS ARC FastExport and FastLoad
Copy all tables in the Teradata RDBMS to a different Teradata RDBMS ARC
Load an identity column table TPump (in ROBUST mode) BTEQ .IMPORT

B - 14 Teradata RDBMS Database Administration

Appendix B: Import/Export Utilities

Monitoring a FastLoad or MultiLoad Job

Monitoring a FastLoad or MultiLoad Job

This section describes how the nature of work performed during the data loading phase and the table processing phase of a FastLoad or MultiLoad job determines where and when the work is charged to the different sessions. Consequently, the pattern of work charged to different sessions causes Teradata Manager to display resource usage of data in a particular way.

LSN

When you run a FastLoad or MultiLoad job, you are logged onto a Teradata Structured Query Language (SQL) session and also under the same user name to n number of FASTLOAD/MLOAD sessions. The LSN is associated with each session when it logs on and identifies a collection of sessions performing the same job. All sessions that are associated with the same job—whether Teradata SQL, FASTLOAD, or MLOAD sessions—are logged on as the same user and have the same LSN. If you want to see the total impact of a FastLoad or MultiLoad job, you must calculate the total impact of all sessions reported with the same LSN.

Resource Usage

For those sessions in which work is charged to AMPs, Teradata Manager displays the following resource usage:

• AMPState or PEState is non-idle.

This typically means that AMPState may be ACTIVE or BLOCKED.

For Teradata SQL sessions, PEState may be PARSING-WAIT, PARSING, ACTIVE, or BLOCKED. For FASTLOAD or MLOAD sessions, PEState is always UNKNOWN.

• AMPCPUSec and AMPIO (logical Input/Output (I/O)) show resource usage.

Understanding that these values are affected by the charging scheme helps explain the impact of resource usage or work charged in the next two tables.

Resource Usage in a FastLoad Job

The following table describes the two primary phases of a FastLoad job. In the data transfer phase, the system completely loads data from the client to the individual AMP associated with each FASTLOAD session. The system performs most of the work during the n FASTLOAD sessions and charges that work to the AMPs.

The system also performs a small amount of setup work for the operation during the Teradata SQL session. When the system is not performing this setup work, AMPState or PEState looks idle.

B - 16

Teradata RDBMS Database Administration Appendix B: Import/Export Utilities

Monitoring a FastLoad or MultiLoad Job

Phase 2 is the end loading phase, when the system completes data transfer to the AMP from the client, and the AMPs insert data into the table. The system performs work mainly during the Teradata SQL session and charged primarily to the AMPs. Although AMPs or Parsing Engines (PEs) are accumulating data in the Teradata SQL session, you may not notice the accumulation of data for a few sampling periods, depending on the size of the FastLoad job or the sampling rate.

FastLoad Phases Start of FastLoad Phase 1 Teradata SQL Session n FASTLOAD Sessions
Phase 1 (data transfer) When system starts to process BEGIN LOADING statement • The system performs a small amount of work. • AMPState or PEState looks IDLE most of the time and shows resource usage. • System charges work to AMPs. • In Teradata Manager, AMPState or PEState is non-idle most of time; AMPCPU and AMPIO show resource usage.
Phase 2 (inserting, error checking) When system starts to process END LOADING statement • System charges work to AMPs. • In Teradata Manager, AMPCPU or PECPU and AMPIO show resource usage.

Phase 1 and Phase 2 can be executed in separate jobs. It is possible to execute multiple Phase 1 jobs, feeding data into one table, followed by one Phase 2 job.

Resource Usage in a MultiLoad Job

The following table describes the two primary phases of a MultiLoad job.

• In the acquisition phase, the system loads data from the client to the individual AMP associated with each MLOAD session. The system performs most of the work during the MLOAD sessions and charges it to the AMPs. The system also performs a small amount of setup work for the operation during the Teradata SQL session. When the system is not performing this setup work, AMPState or PEState looks idle.
Previous << 1 .. 188 189 190 191 192 193 < 194 > 195 196 197 198 199 200 .. 218 >> Next