SQl SGA 整理
--查看诊断位置信息
select * from v$diag_info;
--查看sga中内存分配信息
select * from sys.x$ksmfs;
--查看内存块还剩余多少
select pool,name,bytes/1024/1024 MB from v$sgastat where name='free memory';
--查看共享池的使用情况比率
select to_number(v$parameter.value) value,v$sgastat.bytes/1024/1024 "v$sgastat MB",
(v$sgastat.bytes/v$parameter.value)*100 "percent free"
from v$sgastat,v$parameter where v$sgastat.name='free memory' and v$parameter.name='shared_pool_size'
and v$sgastat.pool='shared pool';
--查看SGA内各个易失存储器块的情况
select * from v$sga_dynamic_components
--查询动态调整SGA内存块还有多少可使用空间
select * from v$sga_dynamic_free_memory;
--SGA信息
select * from v$sgainfo
--可根据此视图调整SGA大小
select * from v$sga_target_advice
PGA的内存命中：
SELECT name profile,cnt,decode( total, 0, 0, round( cnt * 100 / total)) percentage
FROM ( SELECT name, value cnt, ( SUM( value ) OVER()) total
FROM v$sysstat
WHERE name LIKE 'workarea exec%');
-- 数据缓冲区高速缓存
SELECT physical_reads, db_block_gets, consistent_gets, NAME,
100 * ( 1 - ( physical_reads / (consistent_gets + db_block_gets - physical_reads))) "Data Buffer Hit Ratio"
FROM v$buffer_pool_statistics;
-- 重做日至缓冲区
SELECT a.VALUE redo_entries, b.VALUE redo_buffer_allocation_retries,
ROUND ((1 - b.VALUE / a.VALUE) * 100, 4) log_buffer_ratio
FROM v$sysstat a, v$sysstat b
WHERE a.NAME = 'redo entries' AND b.NAME = 'redo buffer allocation retries';
-- 数据字典高速缓存
SELECT SUM (pinhits) / SUM (pins) * 100 "hit radio"
FROM v$librarycache;
-- 库高速缓存
SELECT TO_CHAR (ROUND ((1 - SUM (getmisses) / SUM (gets)) * 100, 1)) || '%' "Dictionary Cache Hit Ratio"
FROM v$rowcache;
-- 排序
SELECT a.VALUE disk_sort, b.VALUE memory_sort, ROUND ((1 - a.VALUE / (a.VALUE + b.VALUE)) * 100, 4) sort_ratio
FROM v$sysstat a, v$sysstat b
WHERE a.NAME = 'sorts (disk)' AND b.NAME = 'sorts (memory)';
--找出相关的sql根据系统pid
select se.username,se.machine,sq.cpu_time,sq.sql_text from
v$process p,v$session se,v$sqlarea sq
where p.addr=se.paddr and se.sql_hash_value=sq.hash_value and p.addr='&pid';
--列出cpu_time top 10
select cpu_time,sql_text
from (select sql_text,cpu_time,
rank() over (order by cpu_time desc) exec_rank
from v$sql
)
where exec_rank <=10;
--执行次数最多的top 10
select sql_text,executions
from (select sql_text,executions,
rank() over
(order by executions desc) exec_rank
from v$sql)
where exec_rank <=10;
