xfs spanning over ssd and hdd

I have a slow and big hdd and a fast but small ssd and want to test the following setup but don't know if it's possible.

Hi.

I have a slow and big hdd and a fast but small ssd and want to test the following setup but don't know if it's possible.

Use LVM to concatenate the ssd and the hdd linearly. Create a xfs filesystem on this device such that the sdd is filled first, i.e. data is written to the ssd as long as there is free space, otherwise the data is written to the hdd.

I have applications which may benefit from this setup but I am not sure so I need to do some benchmarks.

Thanks for your help
Matthias

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Le Mon, 12 May 2014 14:58:58 +0200 vous écriviez:

Quoted 2 lines

I have a slow and big hdd and a fast but small ssd and want to test the following setup but don't know if it's possible.

This doesn't make much sense. If you want to speed up your HDD by using the SSD as a cache, you can set up one of the numerous block-cache systems available for Linux: bcache, enhance IO, FlashCache...

Quoted 4 lines · Matthias Neuer

Hi.

I have a slow and big hdd and a fast but small ssd and want to test the following setup but don't know if it's possible.

Quoted 3 lines

Use LVM to concatenate the ssd and the hdd linearly. Create a xfs filesystem on this device such that the sdd is filled first, i.e. data is written to the ssd as long as there is free space, otherwise the data is written to the hdd.

I have applications which may benefit from this setup but I am not sure so I need to do some benchmarks.

XFS doesn't fill from the front, so you can't configure things to fill the HDD first.

Files in new directories rotor around the allocation groups on the filesystem, so all regions of the fs are filled more or less evenly.