17.05 - File System: Miscellaneous Write Ahead Logging Columns - Teradata Database

Teradata Vantageā„¢ - Resource Usage Macros and Tables

prodname
Advanced SQL Engine
Teradata Database
vrm_release
17.00
17.05
created_date
June 2020
category
Administration
User Guide
featnum
B035-1099-170K

These columns identify the log-based file system recovery scheme in which modifications to permanent data are written to a log file, the WAL log.

Column Name Mode Description Data Type
FileTJAppends count Number of times transient journal records were appended to the WAL log. A single append call can append multiple transient journal rows. A transient journal append by itself does not imply a write of a WAL block, nor a WAL Cylinder Index (WCI) modification. FLOAT
FileTJFlush count Number of times a request to force transient journal records within the WAL log to be written to disk is issued. An increment of this counter may or may not result in an I/O depending on whether the request was to flush records that were already on disk. FLOAT
FileWAppends count Number of times a record was appended to the WAL log. A single append call can append multiple rows. Subtracting FileTJAppends from this counter results in the number of times non-transient journal rows were appended to the WAL log. FLOAT
FileWDBCreates count Number of WAL data blocks created. The block can contain either TJ records, WAL records or both FLOAT
FileWFlush count Number of times a request to force any record in the WAL log to be written to disk is issued. An increment of this counter may or may not result in an I/O depending on whether the request was to flush records that were already on disk. Subtracting FileTJFlush from this counter results in the number of times a non-transient journal WAL flush was issued. FLOAT
FileWRowDelete count Number of times rows were deleted from the WAL log. FLOAT
FileWTabDelRa count Number of requests for a WAL multi-row delete. FLOAT