globus数据管理服务

globus数据管理服务内容摘要：

有可能是多个用户同时进行，使最后写的用户生效 • Append：对文件的添加，直接对远端文件的操作 , 远端立刻改变。 允许多个用户同时操作，但并发写是隔行进行的 网格计算－ Grid Computing 肖侬 File cache • “File open” 将远程文件传输到本地 cache 避免多个本地进程对同一文件的重复打开 • Cache与用户相关，允许用户通过本地资源管理工具对其进行管理 程序通过 cache API 访问文件 cache • 用户可以通过 GRAM远程管理 cache 一个用户可拥有多个 cache ，每个 Cache对应一个条目，记录打开的数目，关闭减少数目，当数目为 0，当该 cache文件将被删除。 网格计算－ Grid Computing 肖侬 三种安全认证方式 • 普通的匿名 ftp、 方式，即没有认证 • 进程之间进行的 GSI认证 • 未来还将发展到基于 SSL认证的 ftp或 访问 网格计算－ Grid Computing 肖侬 工作流程 globusjobrun Local Machine Remote Machine DUROC GASS Server GRAM Client GSI GRAM Gatekeeper GSI GRAM JobManager GASS Client App Nexus GRAM Client GSI MultiRSL Request Remote Machine GRAM Gatekeeper GSI GRAM JobManager GASS Client App Nexus Single RSL Single RSL Parse 网格计算－ Grid Computing 肖侬 GASS RSL Extensions • executable, stdin, stdout, stderr can be local files or URLs • executable and stdin loaded into local cache before job begins (on frontend node) • stdout, stderr handled via GASS append mode • Cache cleaned after job pletes 网格计算－ Grid Computing 肖侬 GASS/RSL Example amp。 (executable= (stdin= (stdout=/home/bester/output) (stderr= 网格计算－ Grid Computing 肖侬 GASS API • GLOBUS GASS_CACHE API • GLOBUS GASS FILE ACCESS API • GLOBUS GASS SERVER API • GLOBUS GASS SERVER_EZ API • GLOBUS GASS CLIENT API 网格计算－ Grid Computing 肖侬 GASS File Access API • Minimum changes to application • globus_gass_open(), globus_gass_close() Same as open(), close() but use URLs instead of filenames Caches URL in case of multiple opens Return descriptors to files in local cache or sockets to remote server • globus_gass_fopen(), globus_gass_fclose() 网格计算－ Grid Computing 肖侬 Remove cache reference Upload changes Modified no yes globus_gass_open()/close() Download File into cache open cached file, add cache reference URL in cache? no yes globus_gass_open() globus_gass_close() 网格计算－ Grid Computing 肖侬 globus_gass_transfer • Common API for transferring remote files/data over various protocols  and currently supported ftp will be supported in future release • Supports put and get operations on an URL • Allows for efficient transfer to/from files or direct to/from memory • Allows any application to easily add customized file/data service capabilities 网格计算－ Grid Computing 肖侬 globus_gass_copy • Simple API for copying data from a source to a destination URL used for source and destination (s), (gsi)ftp, file When transferring from ftp to ftp, it uses 3rd party transfer (. client mediated, direct servertoserver transfer) • globusurlcopy program is simple wrapper around the globus_gass_copy API 网格计算－ Grid Computing 肖侬 globusgassserver • Simple file server Run by user wherever necessary Secure protocol, using GSI APIs for embedding server into other programs • Example globusgassserver –r –w t r: Allow files to be read from this server w: Allow files to be written to this server t: Tilde expand (~/…  $(HOME)/…) help: For list。