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对在ARM CPU上运行的oracle数据库进行分析,判断大小字节序问题
从系统上lscpu看是小字节序
[root@xifenfei ~]# lscpu Architecture: aarch64 CPU op-mode(s): 32-bit, 64-bit Byte Order: Little Endian CPU(s): 8 On-line CPU(s) list: 0-7 Thread(s) per core: 1 Core(s) per socket: 8 Socket(s): 1 NUMA node(s): 1 Vendor ID: ARM Model: 1 Model name: Cortex-A76 Stepping: r4p1 BogoMIPS: 125.00 NUMA node0 CPU(s): 0-7 ………… [root@xifenfei ~]#
从dbid分析字节序问题
数据库中查看dbid值
SQL> select name,dbid,PLATFORM_ID,PLATFORM_NAME from v$database; NAME DBID PLATFORM_ID --------- ---------- ----------- PLATFORM_NAME -------------------------------------------------------------------------------- ARMDB 1195886419 23 Linux OS (AARCH64)
bbed查看dbid值
BBED> p kcvfh.kcvfhhdr.kccfhdbi ub4 kccfhdbi @28 0x4747c753 BBED> set count 16 COUNT 16 BBED> d File: /tmp/system01.dbf (0) Block: 1 Offsets: 28 to 43 Dba:0x00000000 ------------------------------------------------------------------------ 53c74747 41524d44 42000000 03040000 <32 bytes per line>
从这里可以看出来dbid(1195886419)是倒序存储的,也就证明了arm linux上面运行的oracle 是小字节序的.