Re: Stability status of btrfs-convert...
At 06/22/2017 07:31 PM, Austin S. Hemmelgarn wrote: On 2017-06-22 05:37, Shyam Prasad N wrote: Hi, I'm planning to use the btrfs-convert tool to convert production data in ext4 filesystem into btrfs. What is the stability status of this feature? As per the below link, this tool is not in frequent use in latest linux kernels. https://btrfs.wiki.kernel.org/index.php/Conversion_from_Ext3 Can I know the reason why? Is it because most existing ext4 filesystems are already converted? Is this tool supported, at least? Can I use this tool as a part of software upgrade to change the data filesystem to btrfs? Yes, it's supported, but unless you need the ability to switch back as quickly as possible, you are almost certainly better off restoring data from a fresh backup onto a new BTRFS filesystem than you are converting it in-place. I have heard of no currently extant bugs in btrfs-convert, but they usually don't show up immediately, and even if there are no bugs, you still end up with a very sub-optimal on-device layout which isn't even completely fixed by deleting the ext4 metadata and re-balancing, and that will in turn hurt performance somewhat. At a minimum, I would suggest running e4defrag over the whole filesystem prior to converting, as that will at least reduce the degree of fragmentation you start with. Although the tool *seems* stable in recent releases, but Austin is right: The converted btrfs extent layout is not the same as normal btrfs. The difference is: 1) Chunk fragments Due to the fact that btrfs MUST put all old ext* data into DATA chunks, data chunk size is smaller than normal btrfs. Although this can be somewhat addressed by deleting ext* subvolume and then do a balance. 2) More shared extents Unlike normal btrfs usage, convert create as large extent as possible to cover all ext* used data, then create file/dir layous reusing (reflinking) the those large extents. This heavy use of reflink is normally observed in dedupe, but without any space saving. The behavior itself is completely valid for btrfs, but this makes us quite hard to free disk space. Just deleting ext* subvolume can't really free much space now. Defrag should handle it but it's not working for shared extents for a long time. So the short conclusion is: a) Convert is good if you want to try btrfs using old ext* data As you can rollback without losing any data. And it's super fast compared to copying data from backup. b) You can use converted btrfs without problem for a short time The converted btrfs is a completely valid btrfs, although not as normal as original btrfs. You can take full advantage of btrfs features, from snapshot to offline dedupe. c) If you want to use converted btrfs in long term, at least keep an eye on the available space. Converted btrfs layout makes it hard to free space of ext* data. And there is no working defragmentation for shared extent, user should pay extra attention of the available space. Thanks, Qu -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Stability status of btrfs-convert...
On Thu, Jun 22, 2017 at 06:48:53PM +0530, Shyam Prasad N wrote: > The disks that I need to convert could have anywhere from a few GBs to a > maximum of 4 TB. I plan to add the btrfs-convert to a script which does a > software upgrade. (The older version used to store data in extra, we've > moved to btrfs in the newer version). I do have a backup in case I need it. If you have many of them, splendid! You can do one or a few, then see if they explode. No sudden fireworks -> can proceed with the rest. -- ⢀⣴⠾⠻⢶⣦⠀ ⣾⠁⢠⠒⠀⣿⡁ A dumb species has no way to open a tuna can. ⢿⡄⠘⠷⠚⠋⠀ A smart species invents a can opener. ⠈⠳⣄ A master species delegates. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Stability status of btrfs-convert...
On Thu, Jun 22, 2017 at 03:07:14PM +0530, Shyam Prasad N wrote: > I'm planning to use the btrfs-convert tool to convert production data > in ext4 filesystem into btrfs. > What is the stability status of this feature? It has been recently (btrfs-progs 4.6) rewritten nearly from scratch. This was a year ago and from the lack of complaints recently it sounds like any major bugs should be ironed out -- assuming you're using a version of -progs new enough. On the other hand, if you'd want use -progs older than that, I'd recommend also using raid5 and qgroups _and_ cat /dev/the_filesystem, so you have no misguided hopes about the safety of your data. :) > Can I know the reason why? Is it because most existing ext4 > filesystems are already converted? Most of us recreate the filesystem from scratch, that's the safer way. Also, defrag + full-balance are slower than just copying everything in, thus the only things to gain are short downtime (both defrag and balance work online) and no need for temp storage. > Is this tool supported, at least? Can I use this tool as a part of > software upgrade to change the data filesystem to btrfs? You do have backups, right? Meow! -- ⢀⣴⠾⠻⢶⣦⠀ ⣾⠁⢠⠒⠀⣿⡁ A dumb species has no way to open a tuna can. ⢿⡄⠘⠷⠚⠋⠀ A smart species invents a can opener. ⠈⠳⣄ A master species delegates. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Stability status of btrfs-convert...
>Is this tool supported, at least? Can I use this tool as a part of >software upgrade to change the data filesystem to btrfs? Yes its supported. If your existing FS is too large (>22TB) we have a bug for it https://bugzilla.kernel.org/show_bug.cgi?id=194795 AFAIK, there are quite number of people converted their EXT4 to BTRFS . IMO, btrfs-convert is fairly stable, especially if you have only GB's of data Cheers, Lakshmipathi.G http://www.giis.co.in http://www.webminal.org -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Stability status of btrfs-convert...
On 2017-06-22 05:37, Shyam Prasad N wrote: Hi, I'm planning to use the btrfs-convert tool to convert production data in ext4 filesystem into btrfs. What is the stability status of this feature? As per the below link, this tool is not in frequent use in latest linux kernels. https://btrfs.wiki.kernel.org/index.php/Conversion_from_Ext3 Can I know the reason why? Is it because most existing ext4 filesystems are already converted? Is this tool supported, at least? Can I use this tool as a part of software upgrade to change the data filesystem to btrfs? Yes, it's supported, but unless you need the ability to switch back as quickly as possible, you are almost certainly better off restoring data from a fresh backup onto a new BTRFS filesystem than you are converting it in-place. I have heard of no currently extant bugs in btrfs-convert, but they usually don't show up immediately, and even if there are no bugs, you still end up with a very sub-optimal on-device layout which isn't even completely fixed by deleting the ext4 metadata and re-balancing, and that will in turn hurt performance somewhat. At a minimum, I would suggest running e4defrag over the whole filesystem prior to converting, as that will at least reduce the degree of fragmentation you start with. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Stability status of btrfs-convert...
Hi, I'm planning to use the btrfs-convert tool to convert production data in ext4 filesystem into btrfs. What is the stability status of this feature? As per the below link, this tool is not in frequent use in latest linux kernels. https://btrfs.wiki.kernel.org/index.php/Conversion_from_Ext3 Can I know the reason why? Is it because most existing ext4 filesystems are already converted? Is this tool supported, at least? Can I use this tool as a part of software upgrade to change the data filesystem to btrfs? Thanks in advance for your help. -- -Shyam -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Status of BTRFS
Ken D'Ambrosio wrote (ao): Edward Ned Harvey wrote (ao): Is it included in any distributions yet? Yes, Fedora is one of the releases that has officially supported it for a while now. been implemented for Arch Linux, so you might see btrfs being an option for that in the next version of the installer :-) I also believe that Ubuntu 10.10 is slated to have it; I think it's in the current alpha, though based on my reading, there are still some rough edges. Btrfs is in Ubuntu 10.10 alpha and that installs and works oke is my experience. Sander -- Humilis IT Services and Solutions http://www.humilis.net -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Status of BTRFS
On Fri, 16 Jul 2010 10:14:49 pm Edward Ned Harvey wrote: Is it included in any distributions yet? You can use it after installation in Ubuntu 10.04. In fact I'm pretty sure it was enabled in the kernel of 9.10 too. It's not (yet) an option for installation though. -- Chris Samuel : http://www.csamuel.org/ : Melbourne, VIC This email may come with a PGP signature as a file. Do not panic. For more info see: http://en.wikipedia.org/wiki/OpenPGP signature.asc Description: This is a digitally signed message part.
Re: Status of BTRFS
On 07/17/2010 11:11 PM, Chris Samuel wrote: On Fri, 16 Jul 2010 10:14:49 pm Edward Ned Harvey wrote: Is it included in any distributions yet? You can use it after installation in Ubuntu 10.04. In fact I'm pretty sure it was enabled in the kernel of 9.10 too. It's not (yet) an option for installation though. It's included as an installation choice with openSUSE 11.3. -- . O . O . O . . O O . . . O . . . O . O O O . O . O O . . O O O O . O . . O O O O . O O O signature.asc Description: OpenPGP digital signature
Status of BTRFS
Is this a good place to get a clue about the status of BTRFS? Like ... Is it usable yet, and stuff like that? Thank you... -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Status of BTRFS
On 16 July 2010 13:55, Edward Ned Harvey ker...@nedharvey.com wrote: Is this a good place to get a clue about the status of BTRFS? Like ... Is it usable yet, and stuff like that? Thank you... -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html It has been in a good state for quite a while. There seems to be quite a lot of people who use it on enterprise-grade hardware and servers that require high reliability. -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
RE: Status of BTRFS
From: Sebastian 'gonX' Jensen [mailto:g...@overclocked.net] On 16 July 2010 13:55, Edward Ned Harvey ker...@nedharvey.com wrote: Is this a good place to get a clue about the status of BTRFS? Like ... Is it usable yet, and stuff like that? It has been in a good state for quite a while. There seems to be quite a lot of people who use it on enterprise-grade hardware and servers that require high reliability. Is it included in any distributions yet? Do you just need to build the latest kernel or something like that? Download the source code, and follow what it says in the INSTALL file? -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Status of BTRFS
On Fri, Jul 16, 2010 at 08:14:49AM -0400, Edward Ned Harvey wrote: From: Sebastian 'gonX' Jensen [mailto:g...@overclocked.net] On 16 July 2010 13:55, Edward Ned Harvey ker...@nedharvey.com wrote: Is this a good place to get a clue about the status of BTRFS? Like ... Is it usable yet, and stuff like that? It has been in a good state for quite a while. There seems to be quite a lot of people who use it on enterprise-grade hardware and servers that require high reliability. Is it included in any distributions yet? Do you just need to build the latest kernel or something like that? Download the source code, and follow what it says in the INSTALL file? Of course it is. Fedora installer allows btrfs since for few releases now. -- Tomasz TorczOnly gods can safely risk perfection, xmpp: zdzich...@chrome.pl it's a dangerous thing for a man. -- Alia -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Status of BTRFS
On 16 July 2010 14:16, Tomasz Torcz to...@pipebreaker.pl wrote: On Fri, Jul 16, 2010 at 08:14:49AM -0400, Edward Ned Harvey wrote: From: Sebastian 'gonX' Jensen [mailto:g...@overclocked.net] On 16 July 2010 13:55, Edward Ned Harvey ker...@nedharvey.com wrote: Is this a good place to get a clue about the status of BTRFS? Like ... Is it usable yet, and stuff like that? It has been in a good state for quite a while. There seems to be quite a lot of people who use it on enterprise-grade hardware and servers that require high reliability. Is it included in any distributions yet? Do you just need to build the latest kernel or something like that? Download the source code, and follow what it says in the INSTALL file? Of course it is. Fedora installer allows btrfs since for few releases now. -- Tomasz Torcz Only gods can safely risk perfection, xmpp: zdzich...@chrome.pl it's a dangerous thing for a man. -- Alia -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Yes, Fedora is one of the releases that has officially supported it for a while now. Additionally an initrd hook for btrfs has just been implemented for Arch Linux, so you might see btrfs being an option for that in the next version of the installer :-) Regards, Sebastian J. -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Status of BTRFS
Yes, Fedora is one of the releases that has officially supported it for a while now. Additionally an initrd hook for btrfs has just been implemented for Arch Linux, so you might see btrfs being an option for that in the next version of the installer :-) I also believe that Ubuntu 10.10 is slated to have it; I think it's in the current alpha, though based on my reading, there are still some rough edges. I think Fedora's actually got a rollback feature, using snapshots, which should be super nice -- hopefully, others come up with similar features to take advantage of btrfs's features. -Ken -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Status of BTRFS
On Fri, Jul 16, 2010 at 07:55:26AM -0400, Edward Ned Harvey wrote: Is this a good place to get a clue about the status of BTRFS? Like ... Is it usable yet, and stuff like that? Use it if you don't care about the data on your box or do regular backups. All of us developers run it on our workstations without much of an issue though. Thanks, Josef -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Status of BTRFS
Am Freitag 16 Juli 2010, 13:55:26 schrieb Edward Ned Harvey: Is this a good place to get a clue about the status of BTRFS? Like ... Is it usable yet, and stuff like that? Thank you... I wouldn't suggest to use it in productive environments. Especially as the error handling is very rudimentarily for now. If you run into errors, you won't be able to repair the filesystem. For productive environments there are also way to much situations where the whole kernel panics instead only the affected filesystem. Another construction area is still the ENOSPC handling. regards, Johannes -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Status of btrfs-unstable-standalone?
I've noticed that the btrfs-unstable-standalone repository hasn't been updated in over three weeks. It seems all active development is taking place on btrfs-unstable. What is happening to the btfs-unstable-standalone repository? Will all future development only be on btrfs-unstable or is there some other reason btrfs-unstable-standalone hasn't been updated? Thanks, Lee -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
