SSD Arrays and using 4k blocks
Some SSD arrays will perform badly or not work at all when used for Database files.
The example below was used with a Violin Memory Array, but the same is can be any of the new SSD vendors.
Note: The solution below will only work on Linux with asmlib and will not work on Solaris 11.1 and db 11.2.03.
For Solaris you have to make sure to use 512 (sector) in vilion and use 4k blocks when installing the Oracle db.
How to move the spfile from 4k to 512b after ASM is installed and configured
SQL> CREATE DISKGROUP DATA 2 EXTERNAL REDUNDANCY 3 DISK '/path/disk1','/path/disk2','/path/disk3' 4 ATTRIBUTE 5 'au_size'='64M', 6 'sector_size'='4096', 7 'compatible.asm' = '11.2', 8 'compatible.rdbms' = '11.2';
- Use asmca To configure the SP (512b) ASM group
- asmcmd -p spget
+DATA/asm/asmparameterfile/registry.253.849973443 - sqlplus / as sysdba
- create pfile=’/usr/grid/spfile-neto.ora’ from spfile=’+DATA/asm/asmparameterfile/registry.253.849973443′;
How and why 4k SPfile will not work
Helpfull asm commends
Get disk sector or block size
select name,state,sector_size,block_size from v$asm_diskgroup; NAME STATE SECTOR_SIZE BLOCK_SIZE ------------------------------ ----------- ----------- ---------- DATA1 MOUNTED 512 4096
Get disk info
select MOUNT_STATUS,HEADER_STATUS,MODE_STATUS,NAME,PATH,TOTAL_MB,FREE_MB from v$asm_disk; MOUNT_S HEADER_STATU MODE_ST NAME ------- ------------ ------- ------------------------------ PATH TOTAL_MB FREE_MB ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- ---------- ---------- CLOSED CANDIDATE ONLINE /dev/rdsk/c0t6001B970285E503D285E503C682A7F14d0 0 0 CLOSED CANDIDATE ONLINE /dev/rdsk/c0t6001B970285E503D285E503CE6A5021Dd0 0 0 CACHED MEMBER ONLINE BH_DATA_0000 /dev/rdsk/c0t6001B970285E503D285E503C682A7F14d0s0 1048565 300723 CACHED MEMBER ONLINE BH_FRA_0000 /dev/rdsk/c0t6001B970285E503D285E503CE6A5021Dd0s0 1042000 804836