Oracle 参数 MAX_MBPS 官方解释，作用，如何配置最优化建议
本站中文解释
_LISTENER
MAX_MBPS_LISTENER参数用于控制单个客户端可以通过监听器传输的最大数据量，有助于减少其它传输消耗和传输瓶颈。它是一个监听器级别参数，有效值范围为0到10,000 Mbps。
若要正确设置MAX_MBPS_LISTENER参数，可以使用如下步骤：
1.查看可以使用的网络速率。
2.根据可用网络速率计算所需传输流量，向下调整传输速率以避免流量过大。
3.调整MAX_MBPS_LISTENER参数的值以控制监听器可以处理的最大数据量，监听器的最大数据量应不大于网络速率。
4.重启监听器，以使其新设置生效。
5.使用监听器特定的指令确认参数已更改： lsnrctl status
6.使用lsnrctl set the max_mbps_listener可以检查最大传输量设置是否正确。
官方英文解释
MAX_MBPS enables you to set the maximum number of megabytes (MB) of I/Os issued per second on a per pluggable database (PDB) basis. This parameter is used to throttle PDB I/Os.
| Property | Description |
|---|---|
|
Parameter type |
Integer |
|
Default value |
0 |
|
Modifiable |
|
|
Modifiable in a PDB |
Yes |
|
Range of values |
|
|
Basic |
No |
|
Oracle RAC |
Different values can be set on different instances. |
DBWR I/Os, control file I/Os, password file I/Os and other critical I/Os are exempted from the throughput limit set by this parameter, but their I/Os are accounted for while throttling. Because of these exemptions, the PDB’s actual I/O rate may sometimes exceed the limit.
This feature is enabled for multitenant container database (CDB) only. The feature is not supported on Oracle Exadata.
This parameter can be set from inside a PDB. If the parameter is set in CDB$ROOT, all the PDBs in that CDB will inherit the parameter value from CDB$ROOT. This parameter cannot be set in a non-CDB environment.
The default value of 0 means that no limits are set on the maximum number of megabytes (MB) of I/Os that can be issued per second in a PDB.
If Oracle processes need to wait because of this IO rate limit, the wait event is resmgr: I/O rate limit.
See Also:
-
“MAX_IOPS”
-
“resmgr: I/O rate limit”
Examples
This example shows how to use SQL statements to set a maximum of 200 megabytes per second on a PDB named CDB1_PDB1:
alter session set container = cdb1_pdb1; alter system set max_mbps = 200;
