catalyst | 易学教程

Spark-SQL adaptive 自适应框架

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一、自适应框架能解决什么问题 1、目前SparkSQL中reduce阶段的task个数取决于固定参数spark.sql.shuffle.partition(默认值200)，一个作业一旦设置了该参数，它运行过程中的所有阶段的reduce个数都是同一个值。而对于不同的作业，以及同一个作业内的不同reduce阶段，实际的数据量大小可能相差很大，比如reduce阶段要处理的数据可能是10MB，也有可能是100GB, 如果使用同一个值对实际运行效率会产生很大影响，比如10MB的数据一个task就可以解决，如果spark.sql.shuffle.partition使用默认值200的话，那么10MB的数据就要被分成200个task处理，增加了调度开销，影响运行效率。 SparkSQL自适应框架可以通过设置shuffle partition的上下限区间，在这个区间内对不同作业不同阶段的reduce个数进行动态调整。通过区间的设置，一方面可以大大减少调优的成本(不需要找到一个固定值)，另一方面同一个作业内部不同reduce阶段的reduce个数也能动态调整参数如下： spark . sql . adaptive . enabled 默认false 自适应执行框架的开关 spark . sql . adaptive . minNumPostShufflePartitions 默认为1

C9800 Controller for Cloud（BRKEWN-2670）

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1、Catalyst9800 Controller的部署类型 Cisco Catalyst 9800 Wireless Controller Appliances（ C9800-80、C9800-40、C9800-L） Cisco Catalyst 9800 Wireless Controller Public and Private Cloud （公有云和私有云） Cisco Catalyst 9800 Series Wireless Controller for SDA（ C9300&9400 Embeded WLC）（当作为Border、Control和Wireless Control的时候，三款设备支持，当Fabric in a Box[设备同时是Edge，Border，Control]的时候，有两款设备可以支持控制器，C9500没有Edge支持选项） Embedded Wireless Controller on Catalyst 9100（ Catalyst9100 AP EWC） 2、未来使用最新的Cisco Wireless Controller的部署结构，都将替换为Catalyst IOS-XE设备 3、硬件特点（硬件设备）无论是Catalyst9800无线控制器还是Catalyst9K的交换机，在硬件上都有一定的提升，例如C9800控制器使用的QFP

思科CISCO 交换机命名规则

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思科交换机的命名规则要比路由的命名规则复杂，看下这些： WS-C2960-24TC-L 、WS-C2950G-24-EI-DC 、WS-C2960-24TT-L 、WS-C3750G-24TS-E 、WS-C3750G-24T-S，我们并没有在交换机的证明发现它们，我们只看到catalyst 2950 series,把它写全是这样的：CISCO catalyst 2950 series，意思是思科cisco 交换2950 系列，catalyst这个单词是思科交换的意思。今天我们要说的是上面说的一长串的命名规则，每个交换机是以型号命名的，因为一个系列的交换机下面的型号实在是太多了。这一长串数字是写在交换机的背面的，仔细看会发现的。下面我们来说说交换机的型号命名规则：交换：交换机的命名一般是WS开头这个是固定的，再下一个字母有两种一个是C一个是X，C代表固化交换机或者机箱，X代表的是模块。下面我们再来看一些开头标红的一长串型号，在这些型号里面有：G，TT，TC，TS，T，E，L，S，DC。下面我们来看它们分别代表什么： G：表示该交换机是千兆的交换机（全部接口都是千兆的） TT：表示该交换机的千兆上连端口是Base-T的（即：Rj45接口） TC：表示该交换机的千兆上连端口是两用的，直接用是Base-T的，可以可以在其上加模块。 TS：表示该37交换机还有千兆扩展插槽。 T

Moving catalyst framework project to another server

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问题 I had moved my Perl catalyst framework project files from my old server to a new one. I have moved each and every file but when I take the url its showing up 404 error. Is there anything else I need to do when the files are moved? Please let me know as its the 1st time I am doing it. Thanks Jitesh 回答1: You need to update the web server, if there is one. Your application was either running as a standalone app with its own PSGI server, or with another PSGI server like Starman, or through an

Understanding spark physical plan

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问题 I'm trying to understand physical plans on spark but I'm not understanding some parts because they seem different from traditional rdbms. For example, in this plan below, it's a plan about a query over a hive table. The query is this: select l_returnflag, l_linestatus, sum(l_quantity) as sum_qty, sum(l_extendedprice) as sum_base_price, sum(l_extendedprice * (1 - l_discount)) as sum_disc_price, sum(l_extendedprice * (1 - l_discount) * (1 + l_tax)) as sum_charge, avg(l_quantity) as avg_qty, avg

What are best practices for deploying a Catalyst application to a production server?

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问题 What is a good way to deploy Catalyst applications to a production server? Currently I simply have a FastCGI dispatch script in the root of the repository and when I want to update the server code, I push the branch to the server. This is quite simple, but not perfect. If the code fails the tests on the server machine (for example because of unsatisfied dependencies), I am left with broken application. How do you deploy your Catalyst applications? Do you have a better way? 回答1: A combination

What are best practices for deploying a Catalyst application to a production server?

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How do I turn Moose objects into JSON for use in Catalyst?

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问题 I have a series of Moose objects that I'm looking to feed to JSON::XS by way of Catalyst::View::JSON. JSON::XS is unable to encode blessed data-structures. I know that there is MooseX::Storage::Format::JSON which can -- kinda -- do what I want; but, it seems pretty overly heavy. What I'm looking for is essentially the same information that XXX.pm provides. I just want the raw-data structures recursively unblessed so JSON::XS (the driver for JSON::Any that C:V:JSON uses internally) can display

OO Design Patterns with Perl

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问题 I am currently planning the design for a new system I will need to code that interacts with a back-end API. I was contemplating object composition and inheritance and decided that the most correct procedure in my situation would be to go with composition over inheritance as my objects have a "has a" relationship to one another and not an "is a". I find now though that because some objects are reliant on other, there may be cases were "object A" has an attribute which is "object B" and an

How do I handle errors in methods chains in Perl?

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问题 What is the best way to deal with exceptions threw in a method chaining in Perl? I want to assign a value of 0 or undef if any of the methods chained throw an exception Code sample: my $x = $obj->get_obj->get_other_obj->get_another_obj->do_something; What the best way to do it? Do I have to wrap in a try/catch/finally statement everytime? The context I want to apply this is: Im working in web development using Catalyst and DBIC and I do a lot of chained resultsets and if some of this

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