Sybase 12.5.1, Руководство пользователя

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CHAPTER 1 Introduction
User’s Guide
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• Other information – this is the only statistic type valid for data items
that represent character strings. For example, Value for Sample for
Object Name returns the name of a table. This statistic type is also the
only one valid for data items that represent values such as IDs and
values for configured parameters, such as Process ID and Code
Memory Size.
•
“Value for Session”
– this statistic type returns a cumulative count of
activity since the start of gathering the data (since the connection was
opened). No calculations are performed. For example, Value for Session
for Page I/O is the number of page I/Os that occurred since the recording
session started.
•
“Rate for Sample”
– this statistic type calculates a rate per second. It returns
the average number of occurrences per second of an activity during the
most recent sample interval. For example, Rate for Sample for Page I/O is
the average number of page I/Os that occurred each second during the
most recent sample interval.
The calculation is:
• “Rate for Session” – this statistic type calculates a rate per second. It returns
the average number of occurrences per second of an activity during the
current recording session. For example, Rate for Session for Page I/O is
the average number of page I/Os that occurred per second since the
recording session started.
The calculation is:
•
“Average for Sample”
– this statistic type calculates an average value per
occurrence of an activity over the most recent sample interval. Only a few
data items can use this statistic type. The meaning of the returned value
depends on the data item. For example, Average for Sample for Procedure
Elapsed Time is the average execution time per execution of a stored
procedure during the most recent sample interval.
Count for the most recent sample interval
Number of seconds in the sample interval
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Count for the session
Number of seconds in the session
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