Viewing Server Performance with PerfMon and the PAL Tool - SQL Server 2012 Internals and Troubleshooting - page 290

The combined view presents a time axis that can be navigated, by selecting a moment when a CPU
spike occurred; the Proi ler trace automatically relocates to the T-SQL that was executing at the time
of the spike.

Using Relog
Relog can be used to create new log i les with a new sampling rate or a different i le format than
existing PerfMon logs. Relog was i rst included in Windows XP, and it can be useful when han-
dling large logs or many surplus counters are included. Additionally, there are situations when a
log contains data for many hours but the time frame of interest is much shorter; Relog can assist in
extracting the interesting time window for easier analysis. Table 10-7 shows a summary of Relog
parameters.

TABLE 10-7: Summary of Relog Parameters

OPTION DESCRIPTION

-?

Displays context-sensitive help

-a Appends output to the existing binary fi le

-c <path [path ...]> Filters counters from the input log

-cf <filename> Filters fi le listing performance counters from the input log. The

default is all counters in the original log fi le.

-f <CSV|TSV|BIN|SQL>

Specifi es the output fi le format

-t <value>

Writes only every n th record into the output fi le. The default is to
write every record.

-o

Specifi es the output fi le path or SQL database

-b <dd/MM/yyyy
HH:mm:ss[AM|PM]>

Begin time for the fi rst record to write into the output fi le

-e <dd/MM/yyyy
HH:mm:ss[AM|PM]>

End time for the last record to write into the output fi le

-config <filename>

Settings fi le containing command options

-q Lists performance counters in the input fi le

-y Answers yes to all questions without prompting

The following sections demonstrate three example scenarios in which Relog would be useful,
including the syntax used.