On Wed, May 2, 2012 at 9:22 AM, Bardur Arantsson <spam@xxxxxxxxxxxxxxx> wrote: > On 05/01/2012 09:35 PM, Martin wrote: >> >> How well does btrfs perform across a mix of: >> >> 1 SSD and 1 HDD for 'raid' 1 mirror for both data and metadata? >> The idea is to gain the random access speed of the SSDs but have the >> HDDs as backup in case the SSDs fail due to wear... AFAIK only zfs officially supports that configuration, using L2ARC and SLOG >> >> The usage is to support a few hundred Maildirs + imap for users that >> often have many thousands of emails in the one folder for their inbox... Some mail programs uses hardlinks, and btrfs has a low limit on maximum number of hardlinks in a directory. If you use one of those programs, better stay away for now. Plus, from my experience, when using the same disk, btrfs will use up more disk I/O compared to ext4, so if you're already I/O-starved, better stick with ext4. >> Or is btrfs yet too premature to suffer such use? >> > > From Kconfig: > > "Btrfs filesystem (EXPERIMENTAL) Unstable disk format" > ^^^^^^^^^^^^ ^^^^^^^^^^^^^^^^^^ > > Btrfs is too immature to use in ANY kind of production-like scenario where > you cannot afford to lose a certain amount of data (i.e. be forced to > restore from backup) AND suffer downtime. > > I don't think email users are going to be thrilled about the prospect of > "lossy" email. Oracle fully supports btrfs for production environment: http://oss.oracle.com/ol6/docs/RELEASE-NOTES-UEK2-en.html http://www.zdnet.com/blog/open-source/oracles-unbreakable-enterprise-kernel-2-arrives-with-linux-30-kernel-btrfs/10588 http://www.oracle.com/us/technologies/linux/index.html -- Fajar -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
