Curve是什么? - Curve云原生软件定义存储 - Curve分布式块存储 - Curve分布式文件存储 - 高性能、易运维、云原生 Interface CBD NBD iSCSI FUSE kernel NFS S3 HDFS Performance First 性能差异大，延迟高  ## FUSE文件IO读写流程 - 场景1 pytorch example 19/p6_1.jpg)  ## FUSE文件IO读写流程 |22642|open(\*/media/ssd/sample/train/m01448764/n01448764\_18026.JPEG\*, 0\_RDONLY) = 4|

CurveFS初步设计见 CurveFS方案设计（总体设计，只实现了部分），目前需细化Client端设计 ## 概述 CurveFS client 向上提供两层接口，分别是 对接fuse，提供通用文件系统接口。对于fuse接口，先前进行了一些调研，见FUSE调研 提供lib库，提供对接分布式数据库接口，这一部分，可参考polarfs的接口，如下图所示。 int pfs_mount(const char *volname pfs_chdir(const char *volpath) int pfs_getwd(char *buf) Figure 3: libpfs interfaces 根据讨论，我们首先对接fuse的lowlevel operators，对于数据库的lib库接口，后续可以在此基础上再做一层对接。lowlevel operators接口一共45个，如下： +init +destroy +lookup +fallocate +readdirplus +copy_file_range +lseek ## 关键接口分析 ## init void (*init) (void *userdata, struct fuse_conn_info *conn); 根据挂载信息，从mds获取文件系统信息（或superblock），块分配器（ bitmap ）和root inode所在的copyset、metaserver

/mds/curvefs_mds wanghai+ 2642837 2589230 0 13:47 pts/156 00:00:00 ./bazel-bin/curvefs/src/client/fuse_client -f -o volume=/fs -o user=test -o conf=/curvefs/conf/curvefs_client.conf /tmp/fsmount ## 问题1：root用户无法访问挂载目录 Permission denied 查阅资料发现这是fuse的一种安全策略，默认是只有filesystem owner拥有该文件系统的访问权限，如果想要其他用户有权访问，需要在挂载参数中指定`-o allow-root`或`-o allow-other`以允许相应用户有权访问该文件系统，如果挂载者不是root还需要在/etc/fuse.conf（/usr/local/etc/fuse.conf）中增加配置项“user 该配置项是无值的）。详见libfuse官方文档：https://github.com/libfuse/libfuse#security-implications # The file /etc/fuse.conf allows for the following parameters: # # user_allow_other - Using the allow_other mount option

"flatten0", "attrs": { "flatten_data": "0", "func_name": "fuse_flatten", "num_inputs": "1", "num_outputs": "1" }, "inputs": "flatten0", "attrs": { "flatten_data": "0", "func_name": "fuse_flatten", "num_inputs": "1", "num_outputs": "1" }, "inputs": "flatten0", "attrs": { "flatten_data": "0", "func_name": "fuse_flatten", "num_inputs": "1", "num_outputs": "1" }, "inputs":

O_TMPFILE：用于生产临时的无名的普通文件，pathname指定一个目录。 ## libfuse open void(* fuse_lowlevel_ops::open)(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi) Open a file Open flags are available in fi->flags file is opened. See fuse_file_info structure in <fuse_common.h> for more details. If this request is answered with an error code of ENOSYS and FUSE_CAP_NO_OPEN_SUPPORT is set in fuse_conn_info.capable, sent to the filesystem process. Valid replies: fuse reply open fuse reply err Parameters req request handle ino the inode number fi file informationfuse_common.h> ## open flags 在curvefs上的测试 在现在的cu

[–include-pads] [–include-zones] [–include-inner-copper] [–include-silkscreen] [–include-soldermask] [–fuse-shapes] [–fill-all-vias] [–no-extra-padthickness] [–min-distance MIN_DIST] [–net-filter VAR] [–user-origin –include-soldermask Include solder mask layers in export as a set of flat faces. –fuse-shapes Fuse overlapping geometry together in export (time consuming). –fill-all-vias Don’t cut via holes [–include-pads] [–include-zones] [–include-inner-copper] [–include-silkscreen] [–include-soldermask] [–fuse-shapes] [–fill-all-vias] [–no-extra-padthickness] [–min-distance MIN_DIST] [–net-filter VAR] [–user-origin

调研moosefs，chubaofs等分布式系统，参考并设计解决上述遗留问题。 当前删除接口代码如下： CURVEFS_ERROR FuseClient::RemoveNode(fuse_req_t req, fuse_ino_t parent, const char *name) { Dentry dentry; CURVEFS_ERROR ret = dentryManager_->GetDentry(parent 义。 这部分内容在fuse的相关接口中也有描述如下： ## * Forget about an inode * This function is called when the kernel removes an inode * The inode's lookup count increases by one for every call to * fuse reply entry and fuse reply create. The nlookup parameter * Note that if a file system will be exported over NFS the * inodes lifetime must extend even beyond forget. See the * generation field in struct fuse_entry_param

[–include-pads] [–include-zones] [–include-inner-copper] [–include-silkscreen] [–include-soldermask] [–fuse-shapes] [–fill-all-vias] [–min-distance MIN_DIST] [–net-filter VAR] [–user-origin VAR] INPUT_FILE faces. –include-soldermask Include solder mask layers in export as a set of flat faces. –fuse-shapes Fuse overlapping geometry together in export(time consuming). –fill-all-vias Don’t cut via holes [–include-pads] [–include-zones] [–include-inner-copper] [–include-silkscreen] [–include-soldermask] [–fuse-shapes] [–fill-all-vias] [–min-distance MIN_DIST] [–net-filter VAR] [–user-origin VAR] INPUT_FILE

org --fuse --LICENSE --README.md --buffer.go --debug.go --error_darwin.go --error_freebsd.go --error_linux.go --error_std.go --fs --serve.go --tree.go --fuse.go --fuse_darwin.go --fuse_freebsd --fuse_freebsd.go --fuse_kernel.go --fuse_kernel_darwin.go --fuse_kernel_freebsd.go --fuse_kernel_linux.go --fuse_kernel_std.go --fuse_linux.go --fuseutil --fuseutil.go --mount.go --mount_darwin.go --mount_freebsd

t。 RBD：RBD通过Linux内核（Kernel）客户端和QEMU/KVM驱动，来提供一个完全分布式的块设备。 Ceph FS: Ceph FS通过Linux内核（Kernel）客户端结合FUSE，来提供一个兼容POSIX的文件系统。 具体的RADOS细节以及RADOS的灵魂CRUSH（Controlled Replication Under Scalable Hashing，可扩展哈希 FS主要有分为Kernel内核驱动和Ceph FS FUSE两种方式，Linux内核从2.6.34版本开始加入了对Ceph FS的原生支持，如果客户端使用的内核版本较低或者一些应用程序依赖问题，也可以通过FUSE（Filesystem in Userspace）客户端来挂载Ceph文件系统。 在下面的章节中会介绍如何创建Ceph FS、如何通过Kernel内核驱动或FUSE挂载Ceph文件系统。 ![Image up {0=ceph1=up:active}, 2 up:standby #### 4.1.3 挂载Ceph FS 在Linux中挂载Ceph FS有两种方式：Kernel Driver和FUSE。 关于FUSE的介绍参见：https://en.wikipedia.org/wiki/Filesystem_in_Userspace。 ## (1) Kernel驱动方式 通过Kernel内核驱动挂载Ceph