how to reduce bufferbloat

Dislike your radiator noise too much? There's no way to solve it? Is there any new way to solve the noise caused by the fan?　　 Let's start by looking at why the noise is generated.1, because the fan's bearing quality is not good, or fan blades uneven weight, causing vibration;2, because the fan, radiator fin engineering design imperfections caused by wind resistance is too large;3, fan speed is too high.Workaround:By lowering the speed of the radiator fan, can greatly

Map ():map()The function receives two parameters, one is a function and the other isIterable>>> L = [I for I in range] #[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]>>> list (map (str, l)) [' 0 ', ' 1 ', ' 2 ', ' 3 ', ' 4 ', ' 5 ', ' 6 ', ' 7 ', ' 8 ', ' 9 ']Build the list with the list generation first,Str is a function converted to a string,The map function applies the STR function to each element of the listReduce ():>>> l[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]>>> from functools import

Aggregation operations reducet reduce (t identity, Binaryoperator Accumulator)Code:int value = Stream.of (1, 2, 3, 4). Reduce (sum, item), sum + item);Or use a method reference:int value = Stream.of (1, 2, 3, 4). Reduce (+, integer::sum);Value results: 101,103,106,110Identity: It allows the user to provide an initial value for a loop calculation. (+)ACCUMULATOR:

filter (function, sequence): Executes function (item) on item in sequence, and the item that executes the result of true is composed of a list/string/ Tuple (depending on the type of sequence).Filter (function or None, sequence), list, tuple, or string: entry is function and list/tuple/string, return value is Item List/tuple/string.map (function, sequence) : Executes function (item) on item in sequence, and the execution result function (item) is made into a list to return.Map (function, sequenc

With the continuous upgrading of hardware configuration, for small and medium sized applications, the space complexity of the algorithm requirements are also relaxed a lot. However, in today's Web2.0 era, the time complexity of the application has a higher demand. What is the time complexity of the algorithm? In summary, it means to choose an algorithm to represent the original operation of the algorithm, the number of repeated execution of the original operation as the time measurement of the

(1) Lambda A lambda is a python that creates an anonymous function in the form of the following syntax: Lambda [arg1[, arg2, ... argn]]: expressionUse examples: #使用法一 fun = lambda x,y:x+y print Fun (1,2) #输出结果为: 3 #使用法二 print (lambda x,y:x+y) (1,2) # Output: 3 #上面法一和法二相当于: def func_1 (x, y): return x + y print func_1 (1, 2) (2) Map () Map (function, sequence): Performs a function (item) on the item in sequence, as the execution result consists of a list return. Examples are as follows: de

A5 as a fire in the domestic webmaster forum, fund-raising news, transactions, forums in one, to maximize the service to the majority of webmaster, let us grass and webmaster free to learn the know-how to build the site. But A5 's role is not limited to this, site everywhere embodies the knowledge of SEO, such as how to layout the site page, and then how to effectively reduce the rate of jump out of the site, in short, we can learn from the A5 to buil

When Word converts to PDF, it finds that the PDF is quite large, in order not to change the PDF content, and try not to change the quality, using the "Save as" feature of Adobe Acrobat, which may reduce the size of the PDF, is a very useful technique to avoid our PDF document from being too large to "slim down" the document. The reduce file Size command allows you to resample and compress the image, delete

definitely more efficient than method 1. However, writing a multi-threaded program is much more difficult than a method. We must synchronize and share data on our own, for example, to prevent two threads from repeating statistical files. Method 3: Submit the job to multiple computers for completion. We can use the method 1 program to deploy it to N machines, then divide the papers into N parts, and one machine runs a job. This method runs fast enough, but it is difficult to deploy it. We need t

Read this article please go out to run two laps, and then brew a pot of tea, while drinking tea, while watching, after reading you on the whole of Hadoop understand.about HadoopHadoop is an open source system that implements Google's cloud computing system, including parallel computing model Map/reduce, Distributed File System HDFs, and distributed database HBase, along with a wide range of Hadoop related projects, including Zookeeper, Pig,chukwa,hive

The reduce built-in function in python is a binary operation function used to perform the following operations on all data in a data set (such as a linked list or tuples): it is passed to the reduce function func () (It must be a binary operation function) first, perform operations on the first and second data in the set, and then use the func () function to calculate the result. finally, an official explan

), then each small file will also be treated as a block, with a map task to complete,When a map task starts and initializes much longer than the logical processing time, it can cause a lot of wasted resources.Also, the number of maps that can be executed at the same time is limited.4. Is it safe to be sure that each map handles close to 128m of file blocks?The answer is not necessarily. For example, there is a 127m file, normally with a map to complete, but this file only one or two small small

About Hadoop Hadoop is an open source system that implements Google's cloud computing system, including parallel computing model Map/reduce, Distributed File System HDFs, and distributed database HBase, along with a wide range of Hadoop related projects, including Zookeeper,pig, Chukwa,hive,hbase,mahout,flume and so on. Here's a detailed breakdown of the concept in this article to let you know exactly what Hadoop is: 1. What is Map/

Python ---- reduce is used in this way.Official explanation: Apply function of two arguments cumulatively to the items of iterable, from left to right, so as to reduce the iterable to a single value. for example, reduce (lambda x, y: x + y, [1, 2, 3, 4, 5]) calculates (1 + 2) + 3) + 4) + 5 ). the left argument, x, is the accumulated value and the right argument,

a map task to complete,When a map task starts and initializes much longer than the logical processing time, it can cause a lot of wasted resources.Also, the number of maps that can be executed at the same time is limited. 4. It's easy to be sure that each map handles close to 128m of file blocks.The answer is not necessarily. For example, there is a 127m file, normally with a map to complete, but this file only one or two small small paragraph, but there are tens of millions of records,If the

), one is the index of the current element (optional), and one is the array object that the current element belongs to.The 3.reduce method returns the final value for each element in the array, in turn, by the method of the callback function.var aa = [3,2,4,1];var bb = aa.reduce(function(total，item){ return total+item;})console.log(bb); // 输出为10Attention issuesThe reduce callback function has four parame

The reduce () method acts as a function accumulator , takes the result of a callback function, and then executes the callback function again with the previous function result and the next data.Reduce (function (Previousvalue,currentvalue,index,array) {return XXX//The function result that needs to be executed,Previousvalue---------Last Value-CurrentValue---------Current ValueIndex------The current valueArray-------Arrays})；[1,2,3,4,5].

When we are editing Word documents, we often encounter situations where the last page of the document is only one or two lines or even a few words, but it takes up a whole page. More than a piece of paper is trivial, that a few lines occupy a page does not look good layout. Instead of trying to decide which words to delete, use Word's "reduce one page" function flexibly. Select Print Preview, click the "Reduce