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Oracle专用服务器的内存结构分布原则

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Jun 07, 2016 pm 04:53 PM

oracledata

一般我们会把oracle实例的内存用到系统物理内存的80%-60%(4G以上内存用到80%以上，2G内存用到60%-70%)s=pga+sga_max_size=80%mem

一般我们会把Oracle实例的内存用到系统物理内存的80%-60%(4G以上内存用到80%以上，2G内存用到60%-70%)
s=pga+sga_max_size=80%memory (对于OLTP系统pga是sga的4分之1，如果是DSS，，则可以各占一半)
db_cache_size=60%sga
shared_pool_size=sga_max_size-db_cache_size-160m 也可以设置为35%sga左右
java_pool_size=64m
large_pool_size=16m
log_buffer=2m

1：4G物理内存

如果为4000m
则
s=3200m
对于OLTP（
sga=s*80%=2560m
db_cache_size=1536m 访问数据时数据的缓冲区、更新数据提交之前的脏数据等
shared_pool_size=864m 放置sql、plsql代码（以提高代码的共享）和数据字典信息（提高数据字典信息的访问速度）
java_pool_size=64m java应用
large_pool_size=16m 备份和恢复时使用，共享服务器时用户session的信息（UGA）（专用服务器时用户的session信息放置在pga中）
log_buffer=2m 日志数据缓冲、归档所用
PGA=640M）

对于DSS（
sga=s*50%=1600m
db_cache_size=960m 访问数据时数据的缓冲区、更新数据提交之前的脏数据等
shared_pool_size=480m 放置sql、plsql代码（以提高代码的共享）和数据字典信息（提高数据字典信息的访问速度）
java_pool_size=64m java应用
large_pool_size=16m 备份和恢复时使用，共享服务器时用户session的信息（UGA）（专用服务器时用户的session信息放置在pga中）
log_buffer=2m 日志数据缓冲、归档所用
PGA=800M）

2：2G物理内存

如果为2000m
则
s=1200m
对于OLTP（
sga=s*80%=960m
db_cache_size=576m 访问数据时数据的缓冲区、更新数据提交之前的脏数据等
shared_pool_size=224m 放置sql、plsql代码（以提高代码的共享）和数据字典信息（提高数据字典信息的访问速度）
java_pool_size=64m java应用
large_pool_size=16m 备份和恢复时使用，共享服务器时用户session的信息（UGA）（专用服务器时用户的session信息放置在pga中）
log_buffer=2m 日志数据缓冲、归档所用
PGA=240M）

对于DSS（
sga=s*50%=600m
db_cache_size=360m 访问数据时数据的缓冲区、更新数据提交之前的脏数据等
shared_pool_size=144m 放置sql、plsql代码（以提高代码的共享）和数据字典信息（提高数据字典信息的访问速度）
java_pool_size=32m java应用
large_pool_size=16m 备份和恢复时使用，共享服务器时用户session的信息（UGA）（专用服务器时用户的session信息放置在pga中）
log_buffer=2m 日志数据缓冲、归档所用
PGA=240M）

3：8G物理内存

如果为8000m
则
s=6400m
对于OLTP（
sga=s*80%=5120m
db_cache_size=3072m 访问数据时数据的缓冲区、更新数据提交之前的脏数据等
shared_pool_size=1864m 放置sql、plsql代码（以提高代码的共享）和数据字典信息（提高数据字典信息的访问速度）
java_pool_size=64m java应用
large_pool_size=16m 备份和恢复时使用，共享服务器时用户session的信息（UGA）（专用服务器时用户的session信息放置在pga中）
log_buffer=2m 日志数据缓冲、归档所用
PGA=1024M）

对于DSS（
sga=s*50%=3200m
db_cache_size=1920m 访问数据时数据的缓冲区、更新数据提交之前的脏数据等
shared_pool_size=1120m 放置sql、plsql代码（以提高代码的共享）和数据字典信息（提高数据字典信息的访问速度）
java_pool_size=64m java应用
large_pool_size=16m 备份和恢复时使用，共享服务器时用户session的信息（UGA）（专用服务器时用户的session信息放置在pga中）
log_buffer=2m 日志数据缓冲、归档所用
PGA=3200M）

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