Data dodania Pytanie
2017-12-09 20:12 Is prefetching triggered by the stream of exact addresses or by the stream of cache lines? »
On modern x86 CPUs, hardware prefetching is an important technique to bring cache lines into various levels of the cache hierarchy before they are exp...
(0) odpowiedzi
2017-12-09 12:12 Performance: efficient reduction of a 2d array over the columns [OpenMP, C] »
I would like to achieve very efficient parallel reduction operation (i.e. summation): each of columns of a 2-dimensional array (memory buffer in row m...
(1) odpowiedzi
2017-12-09 07:12 How to tune parameters of Bagging in R? »
I was wondering when we use the Bagging to do the classification, what parameters can be tuned and can we use the cross-validation to tune it? In the...
(1) odpowiedzi
2017-12-08 20:12 Java's FilterOutputStream adds a performance penalty »
I have a piece of code that's splitting an output stream to two destinations. They're both going to a file, but the second destination will go throu...
(1) odpowiedzi
2017-12-08 13:12 Testing Speed of Various Sorting Algorithms »
I've just started learning about various algorithms, and I'm attempting to write a program that tests the speed between the algorithms and outputs the...
(0) odpowiedzi
2017-12-08 09:12 Reading xlsx file using Java and sjxlsx api. Unable to get the original decimal data from xlxs »
I'm reading xlsx file using SimpleXLSXWorkbook class, below is the code. public static void testLoadALL( ) { SimpleXLSXWorkbook workbook =new S...
(0) odpowiedzi
2017-12-07 19:12 Store forwarding Address vs Data: What the difference between STD and STA in the Intel Optimization guide? »
I'm wondering if any Intel experts out there can tell me the difference between STD and STA with respect to the Intel Skylake core. In the Intel opti...
(2) odpowiedzi
2017-12-07 11:12 Performance dynamic vs Reflection »
I have the following possibilities to retrieve values in a list: using reflection: foreach (var item in items) { var property=item.Fields[fieldNam...
(1) odpowiedzi
2017-12-07 10:12 why does Julia uses column major? is it fast »
I have read many articles on julia and its performance. but no where, i can find clue about why julia team decided to use column major for matrix oper...
(1) odpowiedzi
2017-12-06 07:12 Analyzing spikes in performance measurement »
I have a set of C++ functions which does some image processing related operation. Generally I see that the final output is delivered in 5-6ms time ra...
(3) odpowiedzi
2017-12-06 01:12 Javascript: indexOf slow on high index despite sparse array? »
While running some tests on my site, I ended up with an array that has only 10 String in it, but one with a very high index (600 000 000). Running in...
(1) odpowiedzi
2017-12-06 00:12 Why is += (addition assignment, plus equal) so slow in node? »
In certain versions of node, a += b is significantly slower than a = a + b, but similar in the browser and later versions. What causes them to run so ...
(1) odpowiedzi
2017-12-05 16:12 PostgreSQL database size is not reasonable »
In my postgresql 9.6 instance I have 1 production database. When I query the size of all databases : combit=> Select pg_database.datname,pg_size_...
(0) odpowiedzi
2017-12-05 05:12 Do 128bit cross lane operations in AVX512 give better performance? »
In designing forward looking algorithms for AVX256, AVX512 and one day AVX1024 and considering the potential implementation complexity/cost of fully g...
(1) odpowiedzi
2017-12-05 04:12 JAX WS Server implementation performance issue for Linux JVM? »
I've faced with a very weird problem. The built-in JAX WS server implementation works 100 times slower on linux machines then on Mac OS X or Windows. ...
(1) odpowiedzi
2017-12-04 12:12 Improve speed execution of MySQL select query »
I have 2 MySQL tables with several millions of rows and I'm trying to perform a query selection for get specific data column from both tables. Despite...
(2) odpowiedzi
2017-12-04 10:12 Fatal Exception: java.lang.NoClassDefFoundError: android/view/ViewStructure »
I am building an community directory application for android OS. It is working fine Lollipop onward devices.Appplication has been sometime crashed in ...
(1) odpowiedzi
2017-12-04 01:12 Calculating the outer product for a sequence of numpy ndarrays »
I have a list of 3D points p stored in an ndarray with shape (N, 3). I want to compute the outer product for each 3d point with itself: N = int(1e4) ...
(3) odpowiedzi
2017-12-03 20:12 "Cleaning up" nested if statements »
In a console program I am creating, I have a bit of code that parses through a file. After parsing each line, it is checked for syntax errors. If the...
(3) odpowiedzi
2017-12-03 12:12 Java: create a new variable or do multiple times the same calculation? »
i have this piece of code: // ... if (result[1] / (abs ? res[0] : 1 > highest) { highest = result[1] / (abs ? res[0] : 1); } and I'm wonderi...
(2) odpowiedzi
2017-12-03 01:12 Why The Runtime and the timeit is different in my code in python? »
I wrote below code and try to see how fast my function is. I used timeit. The factorial result prints very fast (less than 1 sec) but the timer (func_...
(0) odpowiedzi
2017-12-02 22:12 Can the Intel performance monitor counters be used to measure memory bandwidth? »
Can the Intel PMU be used to measure per-core read/write memory bandwidth usage? Here "memory" means to DRAM (i.e., not hitting in any cache level). ...
(0) odpowiedzi
2017-12-02 15:12 Python interpreter takes ~12 seconds to start up, all of which is spent in `import pyexpat` »
I am using a Homebrew-installed Python on my Mac (running OS X 10.13.1), and of late, I’ve noticed that the interpreter takes a frustratingly long t...
(0) odpowiedzi
2017-12-02 15:12 SQL Server: Getting all rows 10 minutes from each other »
Hi I have a SQL problem i cannot solve. I am not sure whether this is a problem that can be solved in regular set-based operations. Here it goes: I ...
(1) odpowiedzi
2017-12-01 19:12 Is there any way to increase the efficiency of PySpark outputs? »
I am trying to test the ability of PySpark to iterate over some very large (10s of GBs to 1s of TBs) data. For most scripts I find PySpark to have ab...
(1) odpowiedzi
2017-12-01 19:12 React 16 : componentDidUpdate Warning: Scheduled a cascading update »
I profiled the performance of my application using react redux by following this article by Ben Schwarz. In the user timing section, i get these war...
(1) odpowiedzi
2017-12-01 10:12 Unexpected memory allocation when using array views (julia) »
I'm trying to search for the desired pattern (variable template) in the array X. The length of the template is 9. I'm doing something like: function...
(2) odpowiedzi
2017-11-30 20:11 Looking to speed up loop including pandas operations »
I need help speeding up this loop and I am not sure how to go about it import numpy as np import pandas as pd import timeit n = 1000 df = pd.DataFra...
(2) odpowiedzi
2017-11-30 12:11 Speed up function for creating a list of triangles from mesh in R »
I wrote a function mesh2listri() in R that takes a kxm matrix and a tringulation structure matrix and returns a list where each element is a 3xm matri...
(3) odpowiedzi
2017-11-30 10:11 Slow SQL Query on MATCH sorting by Relevance »
I have the following Query SELECT product.AID, product.ART_ID, product.EAN, productdetails.DESCRIPTION_SHORT, MAX( (1000...
(0) odpowiedzi
2017-11-30 01:11 Fastest way to compare two strings with dynamic white space? »
I have two strings bigstring and smallstring, and each string is a paragraph of words. However in between each word is a bunch of whitespace (\s in re...
(3) odpowiedzi
2017-11-29 10:11 const vs non-const variable with no change in value once assign »
In C++, if value of a variable never gets changed once assigned in whole program VS If making that variable as const , In which case executable code i...
(2) odpowiedzi
2017-11-29 09:11 Find sub-groups associate to a value and count consecutives sub-groups withing each ID »
I am asking your help to design a very efficient solution to rapidly go through a 14kk rows table. Basically, the problem consists of finding for ...
(2) odpowiedzi
2017-11-29 06:11 Can Laravel 5 handle 1000 concurrent users without lagging badly? »
I wanted to know that if 1000 users are concurrently using a website built with laravel 5 and also querying database regularly then how does laravel 5...
(0) odpowiedzi
2017-11-29 00:11 Does Rust's array bounds checking affect performance? »
I'm coming from C and I wonder whether Rust's bounds checking affects performance. It probably needs some additional assembly instructions for every a...
(1) odpowiedzi