内部视图:interval view x$kvii 介绍

内部视图x$kvii 554078    kslerb    event range base 873    kslnbe    # of base events 285    kslnbesess    # of base events in session 382    kslltl    number of latches 2    ksbcpu_static    initial number of CPUs in the system 4096    kcbswc    DBWR max outstanding writes 1    kcbnwp    number of DBWR processes 204    kcbscw    DBWR write chunk 1    kctsat    true if Statically Allocated Thread 1    kctthr    THRead mounted by this instance - zero if none 1    ktsinm    sga shadow value of instance_number 0    rfragns    Global request id for site 其中kslltl为Oracle中父闩的数量，即kslltl=select count(*) from v$latch; ksbcpu_static记录了当前cpu的内核总数。 kcbswc为Oracle单位时间内所能写出的最大块数（Largest # blocks you can write at any given time）实际受限于物理写出能力。 kctthr为当前实例的线程号。 关于这些视图的研究仍有诸多不明确。 附Oracle kernel 层次： Kernel Subsystems:

OPI	Oracle Program Interface
KK	Compilation Layer - Parse SQL, compile PL/SQL
KX	Execution Layer - Bind and execute SQL and PL/SQL
K2	Distributed Execution Layer - 2PC handling
NPI	Network Program Interface
KZ	Security Layer - Validate privs
KQ	Query Layer
RPI	Recursive Program Interface
KA	Access Layer
KD	Data Layer
KT	Transaction Layer
KC	Cache Layer
KS	Services Layer
KJ	Lock Manager Layer
KG	Generic Layer
KV	Kernel Variables (eg. x$KVIS and X$KVII)
S or ODS	Operating System Dependencies