I use a large data frame called exp( file here) in R. In order to improve performance, I suggest that I view the idata.frame() function from plyr. But I think I’m wrong
My original phone is s
Category: Performance
Whether you are a system designer, developer or tester, to build a high-performance system, you need to understand the following concepts: 1. Response time is the time for the system to respond to user requests, and response time is the user’s most intuitive experience of system performance. Therefore, the performance of the system is directly expressed. 2. Concurrent users, within a certain time frame, the largest number of simultaneous online users, that is, the number of peak online users 3. System throughput refers to the number of requests processed by the system within a unit time 4. Think Time, From a business perspective, this time refers to the time interval between each request when the user performs an operation. In order to simulate this time interval during performance testing, the concept of thinking time is introduced to more realistically simulate the user’s operate. In the formula of throughput, F=VU * R / T shows that throughput F is a function of the number of VUs, the number of requests issued by each user R, and time T, and R can be calculated by time T and user thinking time TS Calculation: R = T / TS
Performance – Reflection rendering in IE8
I encountered a problem with React webapp in IE8. In the latest versions of Chrome and FF, the performance is very good. But, don’t you know, the client is running IE8 and the application is runnin
Performance test case
One: Load test-calculate the maximum concurrency In the process of performance testing, we should first design test scenarios to simulate the real business situation, and then pin Design test scr
Deepening – Highway Network in Keras and Thousands of Road – Significant Differences
I used keras and lasagna to implement a highway network, and the keras version has been lower than the lasagna version. I use the same data set and meta parameters in them. This is Keras version co
Configuring unit query performance is not good
I am adding 3 HIVE large tables (billion-row tables). Collected all the statistics, but the performance is still poor (query time is 40 minutes). Can I set any parameters in the HIVE prompt f
Log system from the unsuccessful building day transaction volume
Course download address: https://pan.baidu.com/s/1SZDjQKK6J24eFvgxElS1vA Extraction code: 6nlt
A large-scale transaction system, the transaction target price is streaming data, and the price
Language-independent – Is it really performance loss when capturing abnormalities?
I asked a question about exceptions, and I am very annoyed by those who say that throwing is slow. I have asked in the past in How exceptions work behind the scenes, and I know that in normal code
Performance – Excel 2003: Why do you have a link to other spreadsheets for so long?
My Excel application creates links to other Excel files. It takes about 1 second to create a link to a cell, but I have hundreds of cells to link, so it’s very Slow.
There is no difference in spee
Garbage collection algorithm
There are two types of garbage collection algorithms: reference counting and reachability analysis.
Reference counter: The implementation is very simple. For an object A, as long as any objec
Performance – All contents of the directory in the breadth priority will result in low efficiency
I wrote a Haskell module that lists all the contents of the directory in width-first order. The following is the source code.
module DirElements (dirElem) where
import System.Directory (getDi