I have a distributed VDR system in my house with a lot of disks
that are NFS mounted by VDR PCs in two rooms.
In order to conserve energy, I have used hdparm to set a spin down
delay after which the disks turn themselves off.
When /video/.update is touched (one of the VDR PCs creates/deletes/
edits a recording, I move a recording into a folder, etc.) or when
the vdr program is started, it reads all directories from all disks.
Most of these directories are unchanged, so there really is no need
to spin up the disk just to read a few inode entries.
However, my observation is that they are always spun up.
So my questions are:
1) Is there a bug in the linux kernel that makes it spin up
the disk needlessly even if the data are still in the cache?
2) Is there a way to configure the kernel, so the inode entries
are locked in the cache or at least get a much higher
cache priority than ordinary data?
Thanks and Cheers,
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