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I have been considering bcache and flashcache.

However my friend suggested me something called ZFS. In fact it says that formating disk with ZFS can actually do the exact same thing without kernel remake or whatever.

Here are some resources I found on the web


It seems that it's true though there is no tutorial on how it is actually done

...e you can come up with other great uses, but that almost always involves some sort of intelligent distinction between data that is accelerated with flash and data that is stored on regular disks. The beauty of ZFS is that it does this job automatically for you.

The beauty is exactly what I want.

Okay I am convinced. I got a /sdc as a huge hard disk and I got /sdd as an ssd.

Now how do I set things up so that the /sdd becomes the zil and l2arc and the /sdd becomes real storage?

Can't we arrange that the zil and l2arc are in the same drive?

I am using centosh. Don't know what version.

I think I have a 120GB SSD.

I would like

40GB for L2ARC 40GB for ZIL 40GB for ZIL mirror.

That seems to be reasonable. Datas are cached anyway. If someone write something and before data is written to disk will L2ARC takes it from ZIL?

share|improve this question
what os are you using? – taffer Feb 1 '13 at 8:41
centos I am using centos. How do I know for sure anyway>? – Jim Thio Feb 1 '13 at 9:03
How do I know? uname -a. ZFS is a Solaris filesystem and was ported to BSD later. It is not officially supported on Linux and there are technical and legal issues with ZFS on linux. Switch to Solaris/OpenIndiana or FreeBSD if you want to use ZFS or use bcache on Linux. Also read this and this. – taffer Feb 1 '13 at 9:14
@taffer, zfs is available for Linux as part of the [zfsonlinux](zfsonlinux.org] project, and though it should be considered as experimental like btrfs, it is relatively stable (I did switch from btrfs to zfs a year ago to get better stability) – Stéphane Chazelas Feb 1 '13 at 9:59

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