Re: [GIT PULL] Btrfs updates for 2.6.31-rc
On Thu, Jul 02, 2009 at 03:10:35PM -0400, Chris Mason wrote: Hello everyone, Here are some btrfs updates. Most of them are small bug fixes, but the large commit from Yan Zheng is step one in getting snapshot deletion rolling. There is also has a nice CPU usage reduction for streaming writes to a file. Linus, please pull the master branch of btrfs-unstable: git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable.git master Sorry, I was a two commits off in generating the stats. The code in the btrfs-unstable tree hasn't changed, but here are the correct stats: Chris Mason (3) commits (+15/-9): Btrfs: don't log the inode in file_write while growing the file (+4/-1) Btrfs: fix the file clone ioctl for preallocated extents (+4/-2) Btrfs: honor nodatacow/sum mount options for new files (+7/-6) Yan Zheng (1) commits (+395/-181): Btrfs: update backrefs while dropping snapshot Josef Bacik (1) commits (+11/-1): Btrfs: account for space we may use in fallocate Jiri Slaby (1) commits (+1/-1): Btrfs: fix use after free in btrfs_start_workers fail path Hu Tao (1) commits (+1/-1): Btrfs: fix error message formatting Total: (7) commits fs/btrfs/async-thread.c |2 fs/btrfs/ctree.h|3 fs/btrfs/extent-tree.c | 566 +--- fs/btrfs/file.c |5 fs/btrfs/inode.c| 25 +- fs/btrfs/ioctl.c|6 fs/btrfs/relocation.c |5 fs/btrfs/transaction.c |4 8 files changed, 423 insertions(+), 193 deletions(-) -- 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: [GIT PULL] Btrfs updates for 2.6.31-rc
On Thu, 11 Jun 2009, Chris Mason wrote: Existing filesystems will be upgraded to the new format on the first mount. All of your old data will still be there and still work properly, but I strongly recommend a full backup before going to the new code. Auugh. This is horrible. I just screwed up my system by booting a kernel on this: it worked beatifully, but due to other reasons I then wanted to bisect a totally unrelated issue. While having _totally_ forgotten about this issue, even if I was technically aware of it. .. so I installed a new kernel, and now it won't boot due to couldn't mount because of unsupported optional features (1). In fact, I have no kernel available on that system that will boot, since my normal safe fall-back kernels are all distro kernels that can't boot this either. Ok, so I'll end up booting from a USB stick, and it will all work out in the end, but this does essentially make it entirely impossible to do any bisection on any btrfs system. Double-plus-ungood. Linus -- 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: [GIT PULL] Btrfs updates for 2.6.31-rc
On Fri, Jun 12, 2009 at 02:55:33PM -0700, Linus Torvalds wrote: On Thu, 11 Jun 2009, Chris Mason wrote: Existing filesystems will be upgraded to the new format on the first mount. All of your old data will still be there and still work properly, but I strongly recommend a full backup before going to the new code. Auugh. This is horrible. I just screwed up my system by booting a kernel on this: it worked beatifully, but due to other reasons I then wanted to bisect a totally unrelated issue. While having _totally_ forgotten about this issue, even if I was technically aware of it. .. so I installed a new kernel, and now it won't boot due to couldn't mount because of unsupported optional features (1). In fact, I have no kernel available on that system that will boot, since my normal safe fall-back kernels are all distro kernels that can't boot this either. We learned this lesson the hard way with ext3, a long time ago, although occasionally we've had to relearn it along the way. The normal failure mode is that some user is still using some ancient distribution, (say, Red Hat 8), and for some reason they boot using a Fedora Rescue CD, and are really annoyed when the filesystem is no longer mountable using the 2.4 kernel that comes with their ancient distribution. So my policy at least with ext4 is to *never* add any new patches were the kernel automatically adds some new feature to the compatibility bitmasks. The user should have to explicitly and manually use a userspace program (i.e., tune2fs) to add some new feature. At least initially we had some cases where ext4 would automatically add some new feature flag thanks to a mount option, but I believe we've gotten rid of all of those cases. I'd suggest that btrfs follow the same strategy; yeah, it means you have to keep more backwards compatibility code for longer, but as btrfs matures, it'll definitely be a Good Thing. - Ted -- 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: [GIT PULL] Btrfs updates for 2.6.31-rc
On Fri, Jun 12, 2009 at 02:55:33PM -0700, Linus Torvalds wrote: On Thu, 11 Jun 2009, Chris Mason wrote: Existing filesystems will be upgraded to the new format on the first mount. All of your old data will still be there and still work properly, but I strongly recommend a full backup before going to the new code. Auugh. This is horrible. I just screwed up my system by booting a kernel on this: it worked beatifully, but due to other reasons I then wanted to bisect a totally unrelated issue. While having _totally_ forgotten about this issue, even if I was technically aware of it. .. so I installed a new kernel, and now it won't boot due to couldn't mount because of unsupported optional features (1). In fact, I have no kernel available on that system that will boot, since my normal safe fall-back kernels are all distro kernels that can't boot this either. Ok, so I'll end up booting from a USB stick, and it will all work out in the end, but this does essentially make it entirely impossible to do any bisection on any btrfs system. First off, I'm sorry. I definitely knew this was going to happen to some of the btrfs users. I wanted to get it in as close as possible to 2.6.30 so that it would be close to the good end of the git bisecting. My choices were: 1) No backward compatibility at all 2) Forward rolling (what we did) 3) Maintain the code to write the old and new formats the way Ted suggests. A number of people argued for #1. The problem with #3 is that it explodes our testing matrix even more, and this is already the most complex part of the FS. For the stage Btrfs is at, I think #2 was the best option. Our future format features will be what Ted is describing, explicitly enabled and much more fined grained. I'll try to find some livecd images for usb sticks that support Btrfs, and make links on the btrfs homepage. -chris -- 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
