benchmarking

问题 I have two javascript functions that do same thing: create a menu based on a json object. One function appends all the <ul> and <li> elements to a variable, and then writes the HTML to the document using the method innerHTML The second function create DOM elements through createElement("ul") and appendChild() methods So I want to know which function is faster, but I do not know how to perform a benchmark test in javascript. my first function is buildMenutoString() and the second function is

问题 This is the converse of the problem "Why is String concatenation faster than String.valueOf for converting an Integer to a String?". It is not a duplicate. Rather, it stems from this answer with benchmarks asserting that t.setText(String.valueOf(number)) is faster than t.setText(""+number) , and ChristianB's question as to why that is. 回答1: String addition results in the compiler creating a StringBuilder instance, followed by append calls for each added element, followed by a call to

问题 I'm using LDBC dataset to test execution time in Neo4j 4.0.1, SF = 1, and I use java to connect Neo4j, ResultSummary.resultAvailableAfter() to get the execution time, which is the time to get the result and start streaming. But for the same query, when I run for the first time, the execution time seems reasonable, like hundreds of ms, but when I continue running this same query, the execution time becomes almost 0. I guess it's effect of query cache, but is there any proper approach to test

问题 I'm using LDBC dataset to test execution time in Neo4j 4.0.1, SF = 1, and I use java to connect Neo4j, ResultSummary.resultAvailableAfter() to get the execution time, which is the time to get the result and start streaming. But for the same query, when I run for the first time, the execution time seems reasonable, like hundreds of ms, but when I continue running this same query, the execution time becomes almost 0. I guess it's effect of query cache, but is there any proper approach to test

问题 I recently determined that there are no significant performance gains from using a Dependency Injected DbContext in .NET Core and using async await calls as opposed to creating a new DbContext every time I want to access the DB. But now I need to know why. I did a much more granular test with System.Diagnostics.Stopwatch in my .NET Core 1.1 API services (which the controller is calling) in which I ran the stopwatch only when accessing the DB. The results were surprising. When using the

问题 I am learning rbenchmark package to benchmark algorithm and see the performance in R environment. However, when I increased the input, benchmark result are varied one to another. To show how the performance of algorithm for different input, producing line graph or curve is needed. I expect to have one line or curve that show the performance difference of using different number of input. The algorithm I used, works O(n^2) .In resulted plot, X axis show number of observation of input, Y axis

问题 I have noticed that loading a CSV file using CSV.read is quite slow. For reference, I am attaching one example of time benchmark: using CSV, DataFrames file = download("https://github.com/foursquare/twofishes") @time CSV.read(file, DataFrame) Output: 9.450861 seconds (22.77 M allocations: 960.541 MiB, 5.48% gc time) 297 rows × 2 columns This is a random dataset, and a python alternate of such operation compiles in fraction of time compared to Julia. Since, julia is faster than python why is

问题 I have noticed that loading a CSV file using CSV.read is quite slow. For reference, I am attaching one example of time benchmark: using CSV, DataFrames file = download("https://github.com/foursquare/twofishes") @time CSV.read(file, DataFrame) Output: 9.450861 seconds (22.77 M allocations: 960.541 MiB, 5.48% gc time) 297 rows × 2 columns This is a random dataset, and a python alternate of such operation compiles in fraction of time compared to Julia. Since, julia is faster than python why is

问题 In my understanding "perf_hooks" is a part of Node.js. However when testing with npm test it fails for me with the following (some filenames are changed): Error: ENOENT: no such file or directory, open 'perf_hooks' at Object.openSync (fs.js:465:3) at Object.readFileSync (fs.js:368:35) at SandboxedModule._getCompileInfo (node_modules/sandboxed-module/lib/sandboxed_module.js:265:20) at SandboxedModule._compile (node_modules/sandboxed-module/lib/sandboxed_module.js:245:22) at

问题 I need to read a file one character at a time and I'm using the read() method from BufferedReader . * I found that read() is about 10x slower than readLine() . Is this expected? Or am I doing something wrong? Here's a benchmark with Java 7. The input test file has about 5 million lines and 254 million characters (~242 MB) **: The read() method takes about 7000 ms to read all the characters: @Test public void testRead() throws IOException, UnindexableFastaFileException{ BufferedReader fa= new