Kcachegrind/callgrind is inaccurate for dispatcher functions?

I have a model code on which kcachegrind/callgrind reports strange results. It is kind of dispatcher function. The dispatcher is called from 4 places; each call says, which actual do_J function to...

Can XDebug track separately the time spent for profiler calls?

I am using XDebug as a profiler for a PHP application. I have run into a situation where XDebug changes severely the results in such a degree that they are useless. Here a simplified example to...

How do I open python profile data with kCacheGrind?

I am having trouble examining profile data with qcachegrind on mac.I am using django-extensions to generate the profile data. I am able to open a normal profile log using cProfile in the code...

QCacheGrind source code path wrong

Trying to profile my code with QCacheGrind and everything loads fine but I can't see the source code inside the program. For some reason the source code path is wrong. Right now it is cachegrind...

How do you output call tree profiling for KCacheGrind with ruby-prof for a Rails app?

According to the documentation, you can profile Rails apps http://ruby-prof.rubyforge.org/ I added this to my config.ru if Rails.env.development? use Rack::RubyProf, :path =>...

Does PHP's xdebug and qcachegrind record/report on time spent waiting for a database?

Using PHP 5.5 on Amazon GNU/Linux. Xdebug is recording profile data from a PHP app running via apache worker MPM. When I view profile data with qcachegrind (running on an OS X laptop), very little...

kcachegrind: there is no source available for the following function

I am trying to view the annotated source using $ valgrind --tool=callgrind ./myProgram followed by $ kcachegrind using Ubuntu 12.04 (and I'm having the same problem with $ qcachegrind using Mac...

How to source annotate python when using qcachegrind to process profilestats output

Kcachegrind serves as a wonderful utility to visually represent the hotspot to the source line level when profiling code. I found it pretty useful when micro optimizing my C++ code base. For my...

xdebug with qcachegrind reports "There is no source available for the following function ..."

I am starting to use xdebug in combination with qcachegrind and first tests work well. The log file gets recorded and I can open it with qcachegrind. But now I have the issue that I dot't get...

Why i do not gain performance using ClassMapAutoloader in Zend Framework 2?

In my company we developing a ZF2 application, no programm;-), right now. We are at a point where we want to test some part of the application by bringing it into the public www. We prepared a...

CakePHP slow response on SQL Server find

I have a problem with my app in CakePHP 2.7.1, with Sqlserver Datasource. When I do a find operation on any table, the response time is extremely slow (more than 1 minute). I did the research with...

How do I read the UI of qcachegrind?

I am using qcachegrind to view a Profile log that is created by Xdebug. I can view the file fine, but I have no clue what Im looking at. I have tried Google but I just keep getting installation...

How to make an optional decorator in Python

I have a set of python scripts that I would like to profile with kernprof https://github.com/rkern/line_profiler but I also want to be able to run it during normal execution without kernprof. What...

C++ profiling reveals vector hotspot. How to optimize?

I am profiling some signal processing code using callgrind / qcachegrind involving many operations on std::vector<float>. I'm getting quite a serious hotspot from the Mac OS builtin nearbyint...

qcachegrind "flat profile" dock panel disappeared. how to restore?

I installed qcachegrind on OS X via brew. No problems. I generated a few *.callgrind files and viewed them with qcachegrind. Again, no problem. While viewing one file I accidentally closed the...

QCachegrind is not displaying any data for php profiling, Configuration issue may be

I have installed the xdebug , and qCachegrind, which is the windows ver of KCachegrind.. but could not see any profiling data on this interface. May be i am unable to configure it correctly. Let...

qcachegrind error: Unknown file format. File generated from php xdebug

I am attempting to use xdebug to profile an application written in php7. I've written a script that sets the follow ini settings: ini_set('xdebug.trace_format',1); // Note: I tried 0 and 2 here as...

How to understand qcachegrind results?

I trying to profile my php app but cant understand indicators in qcachegrind. followed screenshot: its function calls of course. but what means columns incl. and self ? how should i recognize...

Callgrind - QCachegrind output: Does "self" represents the cost of a function per call?

I am confused as to how to interpret the "Self" slot in QCachegrind. Is it per call cost of a function or is it the total cost of a function when called x times where x is represented by the slot...

Getting QCacheGrind to display Call Graph

I'm trying to analyze some code using QCacheGrind. I am using it under Anaconda3 (64-bit) on Windows 10. To get things going, as a test, I'm profiling a small piece of code from "Advanced Python...

One-pass algorithm (clarification needed) Why the space complexity is O(1)?

From en.wikipedia: A one-pass algorithm generally requires O(n) (see 'big O' notation) time and less than O(n) storage (typically O(1)), where n is the size of the input. I made a test with...

Install R 3.x via homebrew

The R formula https://github.com/Homebrew/homebrew-core/commits/master/Formula/r.rb was upgraded from version 3.6.3 to 4.0 semi-recently. There are a few backward-incompatible changes in version...