OS block size ?

[chris zeis]

I know that what the blocksize is for each of my volume groups. What is the OS block size?

I'm using RAID and know that I can determine the stripe sizes. The problem is when I request for example 256K worth of data, how does the OS handle the data and in what size?

[Manju Kampli]

Chris,

OS block size, do you mean file system size??. In that case HFS file system default block size is 8KB and vxfs file system default block size is 1KB. you can change them while creating the file system. Hope this answers your question !!

[Bruce Laughlin]

Hi Chris,

As far as LVM is concerned, the last time I checked, all transfers are limited to 128kb. That is, no matter what size your filesystem block size is, if you're using LVM, the LVM layer will xfer data in 128kb blocks max.

Hope this helps,
Bruce

[federico_3]

In order to Know the OS block size you can use:

fstyp -v /dev/vgxx/lvolx

or

df -g /dev/vgxx/lvolx

or

mkfs -m /dev/vgxx/lvolx


federico