成本很高，导致交互分 析和迭代算法开销很大，MPP 数据库采用 Pipline 方式在内存数据流 中处理数据，效率比文件方式高很多。 总结以上几点，MPP 数据库在计算并行度、计算算法上比 Hadoop 更加 SMART，效率更高；在客户现场的测试对比中，Mapreduce 对 于单表的计算尚可，但对于复杂查询，如多表关联等，性能很差，性 能甚至只有 MPP 数据库的几十分之一甚至几百分之一，下图是基于 MapReduce 选择 MPP 还是 Hadoop ？ HadoopMapReduce和SQL-On-Hadoop技术目前都还不够成熟， 性能和功能上都有很多待提升的空间。相比之下，MPP 数据在数 据处理上更加 SMART，要填平或缩小与 MPP 数据库之间的性能 和功能上的差距，Hadoop 还有很长的一段路要走。就目前来看， 我们认为这两个系统都有其适用的场景。 简单来说，如果你的数据需要频繁的被计算和统计、并且你希望具

passwordless SSH from every host to every other host. The gpstop smart shutdown behavior has changed. Previously, if you ran gpstop -M smart (or just gpstop), the utility exited with a message if there were build, install, upgrade, and uninstall Python packages six Python 2 and 3 compatibility library smart-open Utilities for streaming large files (S3, HDFS, gzip, bz2, and so forth) spaCy Large scale natural and 3 compatibility library sklearn A set of python modules for machine learning and data mining smart-open Utilities for streaming large files (S3, HDFS, gzip, bz2, and so forth) soupsieve A modern CSS

passwordless SSH from every host to every other host. The gpstop smart shutdown behavior has changed. Previously, if you ran gpstop -M smart (or just gpstop), the utility exited with a message if there were build, install, upgrade, and uninstall Python packages six Python 2 and 3 compatibility library smart-open Utilities for streaming large files (S3, HDFS, gzip, bz2, and so forth) spaCy Large scale natural and 3 compatibility library sklearn A set of python modules for machine learning and data mining smart-open Utilities for streaming large files (S3, HDFS, gzip, bz2, and so forth) soupsieve A modern CSS

passwordless SSH from every host to every other host. The gpstop smart shutdown behavior has changed. Previously, if you ran gpstop -M smart (or just gpstop), the utility exited with a message if there were build, install, upgrade, and uninstall Python packages six Python 2 and 3 compatibility library smart-open Utilities for streaming large files (S3, HDFS, gzip, bz2, and so forth) VMware Greenplum 6 Documentation and 3 compatibility library sklearn A set of python modules for machine learning and data mining smart-open Utilities for streaming large files (S3, HDFS, gzip, bz2, and so forth) soupsieve A modern CSS

passwordless SSH from every host to every other host. The gpstop smart shutdown behavior has changed. Previously, if you ran gpstop -M smart (or just gpstop), the utility exited with a message if there were build, install, upgrade, and uninstall Python packages six Python 2 and 3 compatibility library smart-open Utilities for streaming large files (S3, HDFS, gzip, bz2, and so forth) VMware Tanzu Greenplum and 3 compatibility library sklearn A set of python modules for machine learning and data mining smart-open Utilities for streaming large files (S3, HDFS, gzip, bz2, and so forth) soupsieve A modern CSS

passwordless SSH from every host to every other host. The gpstop smart shutdown behavior has changed. Previously, if you ran gpstop -M smart (or just gpstop), the utility exited with a message if there were build, install, upgrade, and uninstall Python packages six Python 2 and 3 compatibility library smart-open Utilities for streaming large files (S3, HDFS, gzip, bz2, and so forth) spaCy Large scale natural and 3 compatibility library sklearn A set of python modules for machine learning and data mining smart-open Utilities for streaming large files (S3, HDFS, gzip, bz2, and so forth) soupsieve A modern CSS

passwordless SSH from every host to every other host. The gpstop smart shutdown behavior has changed. Previously, if you ran gpstop -M smart (or just gpstop), the utility exited with a message if there were build, install, upgrade, and uninstall Python packages six Python 2 and 3 compatibility library smart-open Utilities for streaming large files (S3, HDFS, gzip, bz2, and so forth) VMware Tanzu Greenplum Greenplum Database master host as the Greenplum administrative user: $ su - gpadmin 2. Perform a smart shutdown of your Greenplum Database 6.x system (there can be no active connections to the database)

参数不会立即生效，必须等到数据库重启时才能生效。 5. -M，停止数据库的模式，可选值有：smart、fast、immediate，实际上，-M smart、 -M fast和-M immediate分别对应了三种缩写：-s、-f和-i，虽然help中没 有说明，但是命令是这样工作的，详情可以参考gpstop的Python源码。缺省情 况下，是smart模式，gpstop命令会一直等到所有连接都断开才停止数据库，一 般无

and 3 compatibility library sklearn A set of python modules for machine learning and data mining smart-open Utilities for streaming large files (S3, HDFS, gzip, bz2, and so forth) soupsieve A modern CSS administrative user: $ su - gpadmin 2. Terminate any active connections to the database, and then perform a smart shutdown of your Greenplum Database 6.x system. This example uses the -a option to deactivate confirmation is an expensive-to-compute function. However, Greenplum Database’s planner is currently not very smart about such cases. It considers a query to be potentially executable by index-only scan only when

passwordless SSH from every host to every other host. The gpstop smart shutdown behavior has changed. Previously, if you ran gpstop -M smart (or just gpstop), the utility exited with a message if there were build, install, upgrade, and uninstall Python packages six Python 2 and 3 compatibility library smart-open Utilities for streaming large files (S3, HDFS, gzip, bz2, and so forth) spaCy Large scale natural Greenplum Database master host as the Greenplum administrative user: $ su - gpadmin 2. Perform a smart shutdown of your Greenplum Database 6.x system (there can be no active connections to the database)