On Tue, Jul 14, 2015 at 09:05:39AM +0300, Vasiliy Tolstov wrote: > Does it support discards? Yes > Does this announce means that bcache block device > no longer maintained by developers? There's no plural, it's just me :) I've been overly stressed and burned out from a startup gone horribly wrong - I'm going to try to start doing some maintainence of upstream bcache again once I've moved. I apologize for my absence on the list these past months, I've had (and still have) entirely too much to juggle - hint hint, if anyone wants to jump in and help out. > What about performance tests with compared to plain btrfs/ext4? I haven't done much comparison benchmarking yet, I'll post them once I have. If anyone else wants to do some benchmarking I'd love to see the results. (From the testing I have done - untarring the kernel (on a fast device, with the tar file already uncompressed and in kernel so we're purely cpu bound) - bcachefs is equal to ext4 to within the margin of error. On dbench when we're purely cpu bound, bcachefs is roughly 30% off from ext4. I think the majority of that is bcachefs's dirent code being somewhat cpu heavy). The long term goal is to be at least as fast on ext4/xfs for any given workload, and on typical workloads we ought to be faster - and in particular bcachefs should have better and more predictable latency, due to the way journalling works. > Format command have one device, how provide tiering? --tier specifies the tier of the devices that come after it, where the smaller index is the faster tier. Only tiers 0 and 1 are supported for now, that will be increased whenever someone gets around to it. If /dev/sda is your fast device and /dev/sdb is your slow device, run # bcacheadm format -C /dev/sda --tier 1 /dev/sdb bcacheadm format --help gives you the full list of options. > 14 июля 2015 г. 3:58 пользователь "Kent Overstreet" < > kent.overstreet@xxxxxxxxx> написал: > > > Short announcement, because I'm in the process of moving - but I wanted to > > get > > this out there because the code is up and I think it's reasonably stable > > right > > now. > > > > Bcachefs is a posix filesystem that I've been working towards for - well, > > quite > > awhile now: it's intended as a competitor/replacement for ext4/xfs/btrfs. > > > > Current features > > - multiple devices > > - replication > > - tiering > > - data checksumming and compression (zlib only; also the code doesn't > > work with > > tiering yet) > > - most of the normal posix fs features (no fallocate or quotas yet) > > > > Planned features: > > - snapshots! > > - erasure coding > > - more > > > > There will be a longer announcement on LKML/linux-fs in the near future > > (after > > I'm finished moving) - but I'd like to get it a bit more testing from a > > wider > > audience first, if possible. > > > > You need the bcache-dev branch, and the new bcache tools - be warned, this > > code > > is _not_ compatible with the upstream bcache on disk format: > > > > $ git clone -b bcache-dev http://evilpiepirate.org/git/linux-bcache.git > > $ git clone -b dev http://evilpiepirate.org/git/bcache-tools.git > > > > Then do the usual compiling... > > > > # bcacheadm format -C /dev/sda1 > > # mount /dev/sda1 /mnt > > > > The usual caveats apply - it might eat your data, the on disk format has > > _not_ > > been stabilized yet, etc. But it's been reasonably stable for me, and > > passes all > > but 2-3 of the supported xfstests. > > > > Try it out and let me know how it goes! > > > > Also, programmers please check out the bcache guide - feedback is > > appreciated: > > > > http://bcache.evilpiepirate.org/BcacheGuide/ > > > > Thanks! > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-bcache" in > > the body of a message to majordomo@xxxxxxxxxxxxxxx > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > -- To unsubscribe from this list: send the line "unsubscribe linux-bcache" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
