Curve High performance Cloud native Distributed storage system https://www.opencurve.io/Agenda • What is Curve • Use Cases • CurveBS • Key Features • Comparing to Ceph • CurveFS • Comparing • Curve is an distributed storage system • Components • Curve Block Storage (CurveBS) • CurveBS: a high performance cloud native distributed block storage • Curve File System (CurveFS) • CurveFS:

replicas of data. If one replica fails, the system can read and write data successfully on the other two replicas. When two copies fail at the same time, the system cannot determine the failure reason because the actual situation of the system. Estimation of availability and reliability in the three- replicas case Assume that the total number of disks in Curve system is N, the number of replicas is Before Failure). 𝐴𝐹𝑅 = 1 𝑀𝑇𝐵𝐹/（24 ∗ 365） ∗ 100 In CurveBS, the data on one disk is distributed in about 50 copysets, which means when a disk fails, up to 50 other disks will restore the data

Curve integrate to Cloud NativeCurve intro • Curve is an distributed storage system • High performance • Easiser operation • Cloud native • Curve is composed of two parts • Curve Block Storage • CurveBS: a high performance cloud native distributed block storage • Curve File System (CurveFS) • CurveFS: a high performance cloud native file system (Based on CurveBS / S3 compatible Storage)Operator

Easy operation and maintenance ○ High performance ● CEPH ○ Complex and Large amount of codes ○ system maintenance are difficult in corner cases ○ Performance requirements cannot be metAgenda Why develop take awayPerformance in database scenario Solution architecture ● CURVE provides underlying distributed shared storage services ● Polardb for PostgreSQL provides database services Solution features flowOther performance optimizations RAFT protocol Zero data copy pre-created file poolCURVE file system File service middleware Upper-layer applications can access file data in storage pools through

High performance Cloud native Distributed storage system https://www.opencurve.io/Agenda • CurveBS Architecture • CurveBS Topology • CurveBS Data Organization • MetaData Server (MDS) • ChunkServer and expand CurveBS clusters • Use Curve Discover to discover resource changes and to collect the system’s runtime status to operatorCurveFS ArchitectureCurveFS Data OrganizationCurveFS File OrganizationCurveFS and expand CurveFS clusters • Use Curve Discover to discover resource changes and to collect the system’s runtime status to operatorthanksAbout RAFT

* * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either

variable can be used to inform the * kernel about the timestamp granularity supported by the file-system.© XXX Page 13 of 33 * The value should be power of 10. The default is 1, i.e. full * nano-second rlim_max=256*1024}) = 0 lstat("acl.test", {st_mode=S_IFREG|0674, st_size=6, ...}) = 0 getxattr("acl.test", "system.posix_acl_access", "\2\0\0\0\1\0\6\0\377\377\377\377\2\0\6\0\3362\0\0\4\0\4\0\377\377\377\377\20 test", "system.posix_acl_access", "\2\0\0\0\1\0\6\0\377\377\377\377\2\0\6\0\3362\0\0\4\0\4\0\377\377\377\377\20\0\7\0\377\377\377\377 \0\4\0\377\377\377\377", 132) = 44 setxattr("acl.test", "system.posix_acl_access"

kernel issues forget only after the release or releasedir * calls. * * Note that if a file system will be exported over NFS the * inodes lifetime must extend even beyond forget. See the * generation the lookup count for all inodes implicitly drops * to zero. It is not guaranteed that the file system will * receive corresponding forget messages for the affected© XXX Page 5 of 15 * inodes. nlookup); /** * Remove a file * * If the file's inode's lookup count is non-zero, the file * system is expected to postpone any removal of the inode * until the lookup count reaches zero (see description

/foo/bar in CurveBS 2. The address space of the block device /dev/sda maps to chunks of file in the system. For example, chunk1 corresponds to the address space of 0 to 4MB in /dev/sda, and chunk2 corresponds machine to complete the disk write operation. CurveFS architecture Curvefs implements the file system interface based on FUSE. 1. Fs-meta Cluster is used to manage the inode and dentry metadata of

010000000(since linux 2.6.39) #define O_TMPFILE 020000000|O_DIRECTORY #define O_NDELAY O_NONBLOCK(O_NDELAY是在System V的早期版本引入的，后改进为O_NONBLOCK) flags中必须access mode：O_RDONLY, O_WRONLY, O_RDWR其中之一；© XXX Page 4 of 23