load profiles of oracle war

最新推荐文章于 2021-04-14 01:44:32 发布

原创最新推荐文章于 2021-04-14 01:44:32 发布 · 1.2k 阅读

0 ·

CC 4.0 BY-SA版权

oracle 专栏收录该内容

56 篇文章

订阅专栏

本文介绍了Oracle AWR报告中的Load Profile部分，展示了数据库在快照区间内的工作负载活动，包括每秒和每事务的关键指标，如DB Time、Redo大小、逻辑读取等，并解释了这些指标对于理解应用特性的重要性。

Load Profile

This article gives a glimpse of the oracle database workload activity that occurred within the snapshot interval. For example, the load profile below shows that an average transaction generates about 18K of redo data, and the database produces about 4.9K redo per second.

Load Profile              Per Second    Per Transaction   Per Exec   Per Call
~~~~~~~~~~~~         ---------------    --------------- ---------- ----------
      DB Time(s):                7.7                1.8       0.00       0.04
       DB CPU(s):                6.3                1.5       0.00       0.03
       Redo size:           49,542.2           11,460.9
   Logical reads:          449,830.4          104,061.8
   Block changes:              289.0               66.9
  Physical reads:               63.4               14.7
 Physical writes:               21.0                4.9
      User calls:              212.4               49.1
          Parses:               15.5                3.6
     Hard parses:                2.2                0.5
W/A MB processed:            3,643.2              842.8
          Logons:                0.6                0.2
        Executes:            3,322.1              768.5
       Rollbacks:                0.1                0.0
    Transactions:                4.3

The above statistics give an idea about the workload the database experienced during the time observed. However, they do not indicate what in the database is not working properly. For example, if there are a high number of physical reads per second, this does not mean that the SQLs are poorly tuned.

This workload information is intended to be used along with information from other sections of the AWR report in order to learn the details about the nature of the applications running on the system. The goal is to get a correct picture of database performance.

The following list includes detailed descriptions for particular statistics:

Redo size: The amount of redo generated during this report.

Logical Reads: Calculated as (Consistent Gets + DB Block Gets = Logical Reads).

Block changes: The number of blocks modified during the sample interval.

Physical Reads: The number of requests for a block that caused a physical I/O operation.

Physical Writes: Number of physical writes performed.

User Calls: Number of user queries generated.

Parses: The total of all parses; both hard and soft.

Hard Parses: The parses requiring a completely new parse of the SQL statement. These consume both latches and shared pool area.

Soft Parses: Soft parses are not listed but derived by subtracting the hard parses from parses. A soft parse reuses a previous hard parse; hence it consumes far fewer resources.

Sorts, Logons, Executes and Transactions: All self-explanatory.