lvm configuration

[Joe J_1]

Hello all,

I need to configure a logical volume with the following options:
1) Dynamic write scheduling policy
2) Mirror Write Cache Recovery Method
3) File system inodes set to 1024
Is this possible on a 11.00 O/S?

The switches are not available but the lvm book said it can be done?

Thanks
Joe

[Marco Santerre]

Hi Joe,

for sure, I know you'll find the answer to #3 in the mkfs command. You can look under man mkfs_vxfs and you'll find a specific option (-o ninode=n) that will fit your need.

As for the other two, I'm not as certain this is EXACTLY what you are looking for but when looking at the options for lvcreate, I did find a -M option for Mirror Write Cache, which by default is on.

[Jeff Schussele · Accepted solution]

Hi Joe,

1) Use -d p This is default value for lvcreate
2) Use -M y but again this is the default
3) In vxfs filesystems inode allocation is dynamic. You only need to worry about inode counts for HFS filesystems & they're not recommended due to performance issues & lack of journaling.

Rgds,
Jeff

[John Palmer]

As to 3), you can specify the number of inodes to the mkfs command thus:

mkfs -F vxfs -o ninode=1024 /dev/vg??/rlvol?

bear in mind that if you do so, dynamic inode allocation will be disabled so you will be limited to just over 1000 files. This makes sense however for very large filesystems that contain a small number of large files (e.g. databases) because the default number of inodes created occupy about 3% (if I remember correctly) of available filesystem space.

Regards,
John