Ceph v0.90 发布，分布式文件系统
Ceph v0.90 发布，此版本是圣诞节前最后一个开发版本！此版本包括一些 librados 和 librbd 的 API 清理和大量的 OSD，MDS，RGW 和 CRUSH 方面的 bug 修复；OSD gets support for discard（SSDs 方面也有潜在的帮助，但是默认是关闭的）；改进了 ceph-disk。
接下来两个开发版本将会有大量改进，请继续关注！
值得关注的改进：
arch: fix NEON feaeture detection (#10185 Loic Dachary)
build: adjust build deps for yasm, virtualenv (Jianpeng Ma)
build: improve build dependency tooling (Loic Dachary)
ceph-disk: call partx/partprobe consistency (#9721 Loic Dachary)
ceph-disk: fix dmcrypt key permissions (Loic Dachary)
ceph-disk: fix umount race condition (#10096 Blaine Gardner)
ceph-disk: init=none option (Loic Dachary)
ceph-monstore-tool: fix shutdown (#10093 Loic Dachary)
ceph-objectstore-tool: fix import (#10090 David Zafman)
ceph-objectstore-tool: many improvements and tests (David Zafman)
ceph.spec: package rbd-replay-prep (Ken Dreyer)
common: add ‘perf reset …’ admin command (Jianpeng Ma)
common: do not unlock rwlock on destruction (Federico Simoncelli)
common: fix block device discard check (#10296 Sage Weil)
common: remove broken CEPH_LOCKDEP optoin (Kefu Chai)
crush: fix tree bucket behavior (Rongze Zhu)
doc: add build-doc guidlines for Fedora and CentOS/RHEL (Nilamdyuti Goswami)
doc: enable rbd cache on openstack deployments (Sebastien Han)
doc: improved installation nots on CentOS/RHEL installs (John Wilkins)
doc: misc cleanups (Adam Spiers, Sebastien Han, Nilamdyuti Goswami, Ken Dreyer, John Wilkins)
doc: new man pages (Nilamdyuti Goswami)
doc: update release descriptions (Ken Dreyer)
doc: update sepia hardware inventory (Sandon Van Ness)
librados: only export public API symbols (Jason Dillaman)
libradosstriper: fix stat strtoll (Dongmao Zhang)
libradosstriper: fix trunc method (#10129 Sebastien Ponce)
librbd: fix list_children from invalid pool ioctxs (#10123 Jason Dillaman)
librbd: only export public API symbols (Jason Dillaman)
many coverity fixes (Danny Al-Gaaf)
mds: ‘flush journal’ admin command (John Spray)
mds: fix MDLog IO callback deadlock (John Spray)
mds: fix deadlock during journal probe vs purge (#10229 Yan, Zheng)
mds: fix race trimming log segments (Yan, Zheng)
mds: store backtrace for stray dir (Yan, Zheng)
mds: verify backtrace when fetching dirfrag (#9557 Yan, Zheng)
mon: add max pgs per osd warning (Sage Weil)
mon: fix *_ratio units and types (Sage Weil)
mon: fix JSON dumps to dump floats as flots and not strings (Sage Weil)
mon: fix formatter ‘pg stat’ command output (Sage Weil)
msgr: async: several fixes (Haomai Wang)
msgr: simple: fix rare deadlock (Greg Farnum)
osd: batch pg log trim (Xinze Chi)
osd: clean up internal ObjectStore interface (Sage Weil)
osd: do not abort deep scrub on missing hinfo (#10018 Loic Dachary)
osd: fix ghobject_t formatted output to include shard (#10063 Loic Dachary)
osd: fix osd peer check on scrub messages (#9555 Sage Weil)
osd: fix pgls filter ops (#9439 David Zafman)
osd: flush snapshots from cache tier immediately (Sage Weil)
osd: keyvaluestore: fix getattr semantics (Haomai Wang)
osd: keyvaluestore: fix key ordering (#10119 Haomai Wang)
osd: limit in-flight read requests (Jason Dillaman)
osd: log when scrub or repair starts (Loic Dachary)
osd: support for discard for journal trim (Jianpeng Ma)
qa: fix osd create dup tests (#10083 Loic Dachary)
rgw: add location header when object is in another region (VRan Liu)
rgw: check timestamp on s3 keystone auth (#10062 Abhishek Lekshmanan)
rgw: make sysvinit script set ulimit -n properly (Sage Weil)
systemd: better systemd unit files (Owen Synge)
tests: ability to run unit tests under docker (Loic Dachary)
获取 CEPH
Tarball at http://ceph.com/download/ceph-0.90.tar.gz
For packages, see http://ceph.com/docs/master/install/get-packages
For ceph-deploy, see http://ceph.com/docs/master/install/install-ceph-deploy
更多内容请看发行说明。
Ceph是加州大学Santa Cruz分校的Sage Weil（DreamHost的联合创始人）专为博士论文设计的新一代自由软件分布式文件系统。自2007年毕业之后，Sage开始全职投入到Ceph开 发之中，使其能适用于生产环境。Ceph的主要目标是设计成基于POSIX的没有单点故障的分布式文件系统，使数据能容错和无缝的复制。2010年3 月，Linus Torvalds将Ceph client合并到内 核2.6.34中。
Ceph 中文文档：http://docs.openfans.org/ceph
Ceph 的 4 个模块：
Ceph 生态系统：
来自：http://www.oschina.net/news/58105/ceph-0-90