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Am 16.05.2014 14:03, schrieb Neil Bothwick: |
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> On Fri, 16 May 2014 07:14:27 -0400, covici@××××××××××.com wrote: |
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> |
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>> So far, I have liked lvm, what's the advantage of btrfs over |
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>> lvm? |
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> |
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> I have only looked at btrfs, with a consideration for switching |
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> from ZFS, but it seems to offer the same advantages as ZFS. That |
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> is, it makes things even easier than LVM does. with LVM you can |
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> easily resize volumes and the filesystems on them, but it is still |
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> two or three steps, more if you add RAID into the equation. The |
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> modern filesystems do it all at once. If you need a bigger var, you |
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> just tell it so. And it is exactly the same process for shrinking a |
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> volume, something that can be tricky with LVM because of the need |
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> to handle volume and filesystem separately. |
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btrfs and zfs are removing the various layers we all had to deal with: |
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partitions, logical volumes, raid-arrays, filesystems, and then |
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snapshots etc. |
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With these modern filesystems you are able to basically say: |
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"I have these physical devices/disks, create me a pool of storage with |
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these properties" and then just use that pool in a flexible and |
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dynamic way. |
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Your disk based storage is then usable in a way RAM is, you add it and |
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it is available and you can then use it where you like it. |
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No (or let's say "much less" ...) fixed and hard barriers like |
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partition sizes, if you need space for /var, use it ... if you want to |
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set quotas on /home, just set them for the subvolume, if you add |
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another pair of harddisks, tell btrfs to redistribute redundancy |
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information ("re-balance"). |
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(I see that Alan right now answered basically the same ;-) ). |
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You get checksums for your blocks and the possibility to repair rotted |
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blocks ... you get snapshots within the filesystem, no more slow |
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rsnapshot-crontabs ... |
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I used zfs-fuse back then and learned about the concepts, and it blew |
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my mind already years ago ;-) |
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zfs on linux ... it works fine for me on one server, but I never |
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really wanted it on my main machines (desktop and laptops) although I |
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once even wrote some "how to use zfs on your fully encrypted laptop" |
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for a magazine. It always feels like "suboptimal because it is not in |
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the kernel" to me (think licensing issues here). |
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btrfs is officially in the kernel, still marked "experimental" because |
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it is in active development, after all I read over the last days it |
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should be quite stable to use if you don't run very complex setups or |
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so ... and doing regular backups should be usual for the people in |
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this list, I assume? Distros like SLES come with btrfs as default fs |
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(soon). |
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I migrated ~3 machines to btrfs in the last days and I really love |
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getting rid of all the partitions and raids that grew over the years |
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... for now it is cleaned up and flexible and so far solid. |
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btrfs and zfs have different concepts for various aspects, but |
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basically the same goals. I definitely recommend to get in touch with |
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this generation of filesystems. |
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Stefan |
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