How to determine OS block size for windows or unix

In many times you probably have heard about set the oracle db block size as a multiple of the OS block size. But whenever you ask how I can determine or find OS block size for windows or Unix then many one get stopped. In fact this question is OS related. In this post I will show how I can get OS block.

1)UNIX or Linux System.
On my Solaris Machine,
SQL> !perl -e '$a=(stat ".")[11]; print $a'
8192
On my debian Linux,
$ perl -e '$a=(stat ".")[11]; print $a'
4096

On my Solaris Machine another way,
SQL> !df -g /oracle
/oracle (/dev/dsk/c1d0s3 ): 8192 block size 1024 frag size
Where /oracle is disk partition.

Another example,
SQL> !df -g | grep 'block size'
/ (/dev/dsk/c1d0s0 ): 8192 block size 1024 frag size
/devices (/devices ): 512 block size 512 frag size
/system/contract (ctfs ): 512 block size 512 frag size
/proc (proc ): 512 block size 512 frag size
/etc/mnttab (mnttab ): 512 block size 512 frag size
/etc/svc/volatile (swap ): 4096 block size 4096 frag size
/system/object (objfs ): 512 block size 512 frag size
/lib/libc.so.1 (/usr/lib/libc/libc_hwcap1.so.1): 8192 block size 1024 frag size
/dev/fd (fd ): 1024 block size 1024 frag size
/tmp (swap ): 4096 block size 4096 frag size
/var/run (swap ): 4096 block size 4096 frag size
/oradata1 (/dev/dsk/c1d0s4 ): 8192 block size 1024 frag size
/oracle (/dev/dsk/c1d0s3 ): 8192 block size 1024 frag size
/oradata2 (/dev/dsk/c1d0s5 ): 8192 block size 1024 frag size
/export/home (/dev/dsk/c1d0s7 ): 8192 block size 1024 frag size

2)Windows Machine.
If you use ntfs file system you can use
fsutil fsinfo ntfsinfo drivename: to get information of block size.

c:\>fsutil fsinfo ntfsinfo f:
NTFS Volume Serial Number : 0x1e345b64345b3e49
Version : 3.1
Number Sectors : 0x0000000004a852c0
Total Clusters : 0x0000000000950a58
Free Clusters : 0x00000000003ae433
Total Reserved : 0x0000000000000000
Bytes Per Sector : 512
Bytes Per Cluster : 4096 -- This is OS block size.
Bytes Per FileRecord Segment : 1024
Clusters Per FileRecord Segment : 0
Mft Valid Data Length : 0x000000000d72a000
Mft Start Lcn : 0x00000000000c0000
Mft2 Start Lcn : 0x00000000004a812c
Mft Zone Start : 0x0000000000800720
Mft Zone End : 0x000000000083b920

To get All possible size on windows machine use,
c:\ format /?
In the /A:size you will get the all possible size for both FAT and NTFS file system. Whenever you format a drive you can select default allocation unit as block size.

3)On HPUX issue like "vgdisplay -v /dev/vg01/lvol"

DIM-04503: Message 4503 not found

problem Description

While starting an oracle instance using oradim command or whenever you invoke oradim it fails with DIM-04503 message like below.
E:\xampp\mysql\bin>oradim -start -sid orcl
DIM-04503: Message 4503 not found; product=RDBMS; facility=ORADIM

Cause of the Problem
The problem happened due to incorrect setting of ORACLE_HOME environmental variable. This can also happen if you don't set ORACLE_HOME environmental variable on your windows environment.

Solution of the Problem
Set ORACLE_HOME environmental variable to the location where you have installed oracle software. For example,

E:\xampp\mysql\bin>set ORACLE_HOME=E:\oracle\product\10.2.0\db_2
And now startup database using oradim.
E:\xampp\mysql\bin>oradim -start -sid orcl

Note that, if you have correct ORACLE_HOME setting then invoking oradim will show following output.

C:\Documents and Settings\User>oradim
ORADIM:  [options].  Refer to manual.
Enter one of the following command:
Create an instance by specifying the following options:
     -NEW -SID sid | -SRVC srvc | -ASMSID sid | -ASMSRVC srvc [-SYSPWD pass]
 [-STARTMODE auto|manual] [-SRVCSTART system|demand] [-PFILE file | -SPFILE]
 [-SHUTMODE normal|immediate|abort] [-TIMEOUT secs] [-RUNAS osusr/ospass]
Edit an instance by specifying the following options:
     -EDIT -SID sid | -ASMSID sid [-SYSPWD pass]
 [-STARTMODE auto|manual] [-SRVCSTART system|demand] [-PFILE file | -SPFILE]
 [-SHUTMODE normal|immediate|abort] [-SHUTTYPE srvc|inst] [-RUNAS osusr/ospass]
Delete instances by specifying the following options:
     -DELETE -SID sid | -ASMSID sid | -SRVC srvc | -ASMSRVC srvc
Startup services and instance by specifying the following options:
     -STARTUP -SID sid | -ASMSID sid [-SYSPWD pass]
 [-STARTTYPE srvc|inst|srvc,inst] [-PFILE filename | -SPFILE]
Shutdown service and instance by specifying the following options:
     -SHUTDOWN -SID sid | -ASMSID sid [-SYSPWD pass]
 [-SHUTTYPE srvc|inst|srvc,inst] [-SHUTMODE normal|immediate|abort]
 Query for help by specifying the following parameters: -? | -h | -help

Note that if you set environmental variable using set command from command prompt then it will be set only for that session. If you want to set as permanent basis then,
- Right click on My Computer icon.
- Click on Properties.
- Go to Advanced tab.
- Click on Environmental Variable.
- Now you can set environmental variable permanently for a user or for system.
- Click on New either for a particular user or for system. If you set for system it will affect all users of the machine.
- Two textbox will appear. In the Variable Name field type ORACLE_HOME and in the Variable Value type the path of your oracle home.
- Click ok and you are done.