fork for as many physically different disks you have. not partitions, not directories.

When using RAIDs and/or LVM, that rule is a little bit too simple:

In case of hardware RAIDs (expensive disk controller with dedicated CPU, dedicated RAM, perhaps battery backup), treat each RAID volume as a single disk. The number of physical disks is irrelevant in this case.

In case of software RAIDs (e.g. Linux MD driver, ZFS), things may become compicated. In the most simple case, each RAID volume is composed of several disks containing no or just a single partition, and you can treat each RAID volume as a single disk. If you spread several RAID volumes over several disks (e.g. a /boot RAID-1 using the first partition of each disk and a /data or root RAID-5 using the second partition of each disk), you need to treat the two RAIDs as a single disk. For more advanced setups, things will get successively more complex.

In case of fake RAIDs (cheap disk controller with no CPU, no RAM, just a boot ROM, implementing a BIOS-level software RAID), the hardware RAID rules apply if the fake RAID allows only RAIDs of entire disks. If the fake RAID allows to partition the disks into several RAIDs (I've never seen that), the software RAID rules apply.

If you use LVM on top of the RAID, or even just on top of bare disks, you need to treat all disks (physical or RAID volumes) shared by an LVM set as a single disk.

Alexander

--
Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)

In reply to Re^10: Finding files recursively by afoken
in thread Finding files recursively by ovedpo15

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