O manual de KCachegrind

# O manual de KCachegrind

Josef Weidendorfer `<Josef.Weidendorfer@gmx.de>`

Federico Zenith `<federico.zenith@member.fsf.org>`

Tradutor do proxecto Trasno: Marce Villarino
Revisión 0.5.1 (2009-10-07)

Copyright © 2002-2004 Josef Weidendorfer

Copyright © 2009 Federico Zenith

Aviso Legal

KCachegrind é unha ferramenta de visualización de datos de perfilado, escrita para o entorno KDE.

Capítulo 1. Introdución
Introdución

# Capítulo 1. Introdución

KCachegrind é un navegador dos datos de perfilado producidos por ferramentas de perfilado/tracexamento. Este capítulo explica para que serve o perfilado, como se fai, e dará algúns exemplos das ferramentas de perfilado disponíbeis.

## Perfilado

Cando se desenvolve un programa, un dos últimos pasos a miúdo son as optimizacións do rendimento. Xa que non ten sentido optimizar funcións que sexan raramente usadas, porque sería unha perda de tempo, é preciso saber que partes do programa son usadas a maior parte do tempo.

Para o código secuencial, polo xeral é abondo recoller datos estatísticos das características de execución do programa, como o tempo gastado en cada función e as liñas de código. Isto é chamado "Perfilado". O programa é executado baixo a supervisión dunha ferramenta de perfilado, que dá un resumo dunha execución. En contraste, no código paralelo os problemas de rendimento polo xeral teñen a súa orixe en que un procesador está a esperar datos de outro. Xa que polo xeral non é facil coñecer a orixe deste tempo de espera, neste caso é mellor xerar trazas de eventos con selo temporal. KCachegrind non pode visualizar este tipo de datos.

Tras analisar os datos de perfilado producidos, debera ser sinxelo ver os pontos críticos e pescozos de botella do código: por exemplo, poden comprobarse suposicións acerca do número de chamadas, e optimizar as rexións identificadas como críticas no código. Tras isto, a eficacia das optimizacións debe ser verificada con outro perfilado.

Métodos de perfilado
Métodos de perfilado

## Métodos de perfilado

Para medir con exactitude o tempo decorrido ou rexistrar os eventos que aconteceron durante a execución dun código concreto (isto é unha función), debe inserir medidas adicionais no código, antes e despois da área en concreto. Este código le o tempo ou un reconto globla de eventos, e calcula as diferenzas. Deste xeito, as fontes orixinais deben ser modificadas antes da execución. Isto é denominado Instrumentación. A instrumentación pode ser feita polo propio programador, polo compilador ou polo sistema de execución. Dado que as áreas interesantes polo xeral están aniñadas, o proceso de medida sempre influi no medido. Polo tanto, a instrumentación debe ser feita de xeito selectivo e os resultados teñen que ser interpretados con coidado. Por suposto, isto fai que as análises de rendimento mediante medidas exactas sexa un proceso moi complexo.

Exact measurement is possible because of hardware counters (including counters incrementing on a time tick) provided in modern processors, which are incremented whenever an event is happening. As we want to attribute events to code regions, without the counters, we would have to handle every event by incrementing a counter for the current code region ourself. Doing this in software is, of course, not possible; but, on the assumption that the event distribution over source code is similar when looking only at every n-th event instead of every event, a measurement method whose overhead is tunable has been developed: it is called Sampling. Time Based Sampling (TBS) uses a timer to regularly look at the program counter to create a histogram over the program code. Event Based Sampling (EBS) exploits the hardware counters of modern processors, and uses a mode where an interrupt handler is called on counter underflow to generate a histogram of the corresponding event distribution: in the handler, the event counter is always reinitialized to the n of the sampling method. The advantage of sampling is that the code does not have to be changed, but it is still a compromise: the above assumption will be more correct if n is small, but the smaller the n, the higher the overhead of the interrupt handler.

Outro método de medición consiste en simular os acontecimentos dun sistema informático durante a execución dun certo código, isto é unha simulación guiada pola execución. A simulación sempre se deriva dun modelo de máquina máis ou menos exacto; porén, con modelos de máquinas moi detallados, que dan aproximacións moi exactas á realidade, a duración da simulación pode ser excesivamente alta como para poder ser usada na prática. A vantaxe da simulación é que código de medida/simulación arbitrariamente complexo pode ser inserido no código a medir sen perturbar os resultados. Facer isto directamente antes da execución (o que se chama instrumentación do tempo de execución), usando o binario orixinal, é moi confortábel para o usuario: non é preciso recompilar. A simulación é usábel cando só son simuladas partes dunha máquina cun modelo simples; outra vantaxe é que o resultado producido por un modelo simples polo xeral é máis fácil de comprender: a miúdo, o problema co hardware real é que os resultados inclúen resultados con efeitos de solapamentos de diferentes partes da máquina.

Ferramentas de Perfilado
Ferramentas de Perfilado

## Ferramentas de Perfilado

Most known is the GCC profiling tool gprof: one needs to compile the program with option `-pg`; running the program generates a file `gmon.out`, which can be transformed into human-readable form with gprof. One disadvantage is the required re-compilation step to prepare the executable, which has to be statically linked. The method used here is compiler-generated instrumentation, which measures call arcs happening among functions and corresponding call counts, in conjunction with TBS, which gives a histogram of time distribution over the code. Using both pieces of information, it is possible to heuristically calculate inclusive time of functions, isto é time spent in a function together with all functions called from it.

Para medir exactamente os eventos que acontecen, existen bibliotecas con funcións capaces de ler contadores de rendimento do hardware. A máis coñecida destas é o parche PerfCtr para Linux®, e as bibliotecas independentes da arquitectura PAPI e PCL. Aínda así, unha medición exacta requere de instrumentación do código, como de indicou antes. Pode usar unha das bibliotecas en si ou un sistema de instrumentación automática como ADAPTOR (para instrumentar código fonte FORTRAN) ou DynaProf (para inxectar código mediante DynInst).

OProfile é unha ferramenta de perfilado de sistema para Linux® que usa Mostraxe.

En moitos aspeitos, un xeito cómodo de perfilar é usar Cachegrind ou Callgrind, que son simuladores que usar o framework de intrumentación en tempo de execución Valgrind. Debido a que non hai necesidade de aceder a contadores hardware (o que a miúdo é difícil nas instalacións Linux® actuais), e a que os binarios para perfilar poden ser deixados sen modificar, é unha boa alternativa a outras ferramentas de perfilado. A desvantaxe da simulación - enlentecimento - pode ser reducida facendo a simulación só das partes interesantes do programa, e talvez só unhas poucas iteracións dun bucle. Sen instrumentación de medida/simulación, o uso de Valgrind só ten un factor de enlentecimento no rango de 3 a 5. Ademais, cando só interesan os grafos de chamadas e reconto de chamadas, o simulador da caché pode non ser utilizado.

Cache simulation is the first step in approximating real times, since runtime is very sensitive to the exploitation of so-called caches, small and fast buffers which accelerate repeated accesses to the same main memory cells, on modern systems. Cachegrind does cache simulation by catching memory accesses. The data produced includes the number of instruction/data memory accesses and first- and second-level cache misses, and relates it to source lines and functions of the run program. By combining these miss counts, using miss latencies from typical processors, an estimation of spent time can be given.

Callgrind é unha extensión de Cachegrind que construi ao vóo o grafo de chamadas dun programa, isto é como se chaman entre si as funcións e como acontecen múltiplos eventos ao executar unha función. Tamén pode separar os datos recollidos no perfilado por contextos de fíos e de cadea de chamadas. Pode fornecer datos de perfilado a nível de instrución e permite anotar o código desensamblado.

Visualización
Visualización

## Visualización

As ferramentas de perfilado polo xeral producen grandes cantidades de datos. O motivo de elaborar dunha aplicación de GUI foi poder examinar de riba a baixo o grafo de chamadas, así como poder mudar rapidamente o modo de ordenar as funcións e mostrar os diferentes tipos de eventos.

KCachegrind is a visualization tool for profile data fulfilling these wishes. Despite being programmed first with browsing the data from Cachegrind and Calltree in mind, there are converters available to be able to display profile data produced by other tools. In the appendix, a description of the Cachegrind/Callgrind file format is given.

Besides a list of functions sorted according exclusive or inclusive cost metrics, and optionally grouped by source file, shared library or C++ class, KCachegrind features various views for a selected function, namely:

- unha vista de grafo de chamadas, que mostra unha sección do grafo de chamadas arredor da función escollida,

- unha vista de mapa en árbore, que permite visualizar relacións de chamadas aniñadas, xunto co custo acumulado para detectar rapidamente as funcións problemáticas dun xeito visual,

- vistas de anotacións do código fonte e desensamblado, permitindo ver detalles do custo relacionado coas liñas das fontes e instrución na linguaxe de ensamblaxe.

Capítulo 2. Uso de KCachegrind
Uso de KCachegrind

# Capítulo 2. Uso de KCachegrind

## Xerar datos para visualizar

Primeiro, deberá xerar datos de rendimento medindo aspeitos das características de execución dunha aplicación, usando unha ferramenta de perfilado. KCachegrind non inclui nengunha ferramenta de perfilado, pero pode usala xunto con Callgrind, e mediante convertedores, tamén pode usala para ver os datos producidos por OProfile. Apesar de que este manual non pretende documentar a realización de perfilados con estas ferramentas, na seguinte sección darase unha breve guía introdutoria a elas.

### Callgrind

Callgrind is a part of Valgrind. Note that it previously was called Calltree, but that name was misleading.

The most common use is to prefix the command line to start your application with `valgrind `--tool=callgrind`` , as in:

> `valgrind `--tool=callgrind` `myprogram` `myargs``

At program termination, a file `callgrind.out.`pid`` will be generated, which can be loaded into KCachegrind.

More advanced use is to dump out profile data whenever a given function of your application is called. E.g. for Konqueror, to see profile data only for the rendering of a Web page, you could decide to dump the data whenever you select the menu item View → Reload . This corresponds to a call to `KonqMainWindow::slotReload`. Use:

> `valgrind `--tool=callgrind` `--dump-before=KonqMainWindow::slotReload` `konqueror``

This will produce multiple profile data files with an additional sequential number at the end of the filename. A file without such an number at the end (only ending in the process PID) will also be produced; by loading this file into KCachegrind, all others are loaded too, and can be seen in the Parts Overview and Parts list.

### OProfile

OProfile is available from its home page. Follow the installation instructions on the Web site, but, before you do, check whether your distribution does not already provide it as package (like SuSE®).

System-wide profiling is only permitted to the root user, as all actions on the system can be observed; therefore, the following has to be done as root. First, configure the profiling process, using the GUI oprof_start or the command-line tool opcontrol. Standard configuration should be timer mode (TBS, see introduction). To start the measurement, run `opcontrol `-s``. Then run the application you are interested in and, afterwards, do a `opcontrol `-d``. This will write out the measurement results into files under folder `/var/lib/oprofile/samples/`. To be able to visualize the data in KCachegrind, do in an empty directory:

> `opreport `-gdf` | op2callgrind`

This will produce a lot of files, one for every program which was running on the system. Each one can be loaded into KCachegrind on its own.

Descrición básica da interface de usuario
Descrición básica da interface de usuario

## Descrición básica da interface de usuario

When starting KCachegrind with a profile data file as argument, or after loading one with File → Open, you will see a navigation panel containing the function list at the left; and, on the right the main part, an area with views for a selected function. This view area can be arbitrarily configured to show multiple views at once.

At first start, this area will be divided into a top and a bottom part, each with different tab-selectable views. To move views, use the tabs' context menu, and adjust the splitters between views. To switch quickly between different viewing layouts, use View → Layout → Go to Next (Ctrl+→) and View → Layout → Go to Previous (Ctrl+←).

The active event type is important for visualization: for Callgrind, this is, for example, cache misses or cycle estimation; for OProfile, this is « Timer » in the simplest case. You can change the event type via a combobox in the toolbar or in the Event Type view. A first overview of the runtime characteristics should be given when you select function `main` in the left list; look then at the call graph view. There, you see the calls occurring in your program. Note that the call graph view only shows functions with high event count. By double-clicking a function in the graph, it will change to show the called functions around the selected one.

To explore the GUI further, in addition to this manual, also have a look at the documentation section on the Web site. Also, every widget in KCachegrind has « What's this » help.

Capítulo 3. Conceitos Básicos
Conceitos Básicos

# Capítulo 3. Conceitos Básicos

Este capítulo explica algúns conceitos de KCachegrind, e introduce vocábulos usados na interface.

## O modelo de datos dos datos do perfilado

### Entidades de custo

Cost counts of event types (like L2 Misses) are attributed to cost entities, which are items with relationship to source code or data structures of a given program. Cost entities not only can be simple code or data positions, but also position tuples. For example, a call has a source and a target, or a data address can have a data type and a code position where its allocation happened.

The cost entities known to KCachegrind are given in the following. Simple Positions:

Instruction

  An assembler instruction at a specified address.

Source Line of a Function

  All instructions that the compiler (via debug information) maps to a given source line specified by source file name and line number, and which are executed in the context of some function. The latter is needed because a source line inside of an inlined function can appear in the context of multiple functions. Instructions without any mapping to an actual source line are mapped to line number 0 in file `???`.

Function

  All source lines of a given function make up the function itself. A function is specified by its name and its location in some binary object if available. The latter is needed because binary objects of a single program each can hold functions with the same name (these can be accessed isto é with `dlopen` or `dlsym`; the runtime linker resolves functions in a given search order of binary objects used). If a profiling tool cannot detect the symbol name of a function, isto é because debug information is not available, either the address of the first executed instruction typically is used, or `???`.

Binary Object

  All functions whose code is inside the range of a given binary object, either the main executable or a shared library.

Source File

  All functions whose first instruction is mapped to a line of the given source file.

Class

  Symbol names of functions typically are hierarchically ordered in name spaces, isto é C++ namespaces, or classes of object-oriented languages; thus, a class can hold functions of the class or embedded classes itself.

Profile Part

  Some time section of a profile run, with a given thread ID, process ID, and command line executed.

As can be seen from the list, a set of cost entities often defines another cost entity; thus, there is a inclusion hierarchy of cost entities.

Positions tuples:

- Call from instruction address to target function.

- Call from source line to target function.

- Call from source function to target function.

- (Un)conditional jump from source to target instruction.

- (Un)conditional jump from source to target line.

Jumps between functions are not allowed, as this makes no sense in a call graph; thus, constructs like exception handling and long jumps in C have to be translated to popping the call stack as needed.

### Tipos de evento

Pode definir tipos de evento arbitrario nos datos do perfilado dándolles un nome. O seu custo en relación a unha entidade de custo é un inteiro de 64 bits.

Os tipos de evento cuxo custo estexa especificado nun ficheiro de datos de perfilado son denominados eventos reais. Ademais, pode indicar fórmulas para tipos de eventos calculados a partir de eventos reais, que son chamados eventos herdados.

Visualización do estado
Visualización do estado

## Visualización do estado

The visualization state of a KCachegrind window includes:

- the primary and secondary event type chosen for display,

- the function grouping (used in the Function Profile list and entity coloring),

- the profile parts whose costs are to be included in visualization,

- an active cost entity (isto é a function selected from the function profile sidedock),

- a selected cost entity.

This state influences the views.

Views are always shown for one cost entity, the active one. When a given view is inappropriate for a cost entity, it is disabled: when selecting isto é an ELF object in the group list, source annotation makes no sense.

For example, for an active function, the callee list shows all the functions called from the active one: one can select one of these functions without making it active. Also, if the call graph is shown beside, it will automatically select the same function.

Partes da GUI
Partes da GUI

## Partes da GUI

### Acoples laterais

Sidedocks are side windows which can be placed at any border of a KCachegrind window. They always contain a list of cost entities sorted in some way.

- The Function Profile is a list of functions showing inclusive and exclusive cost, call count, name and position of functions.

- Parts Overview

- Call Stack

### View Area

The view area, typically the right part of a KCachegrind main window, is made up of one (default) or more tabs, lined up either horizontally or vertically. Each tab holds different views of only one cost entity at a time. The name of this entity is given at the top of the tab. If there are multiple tabs, only one is active. The entity name in the active tab is shown in bold, and determines the active cost entity of the KCachegrind window.

### Areas of a Tab

Each tab can hold up to four view areas, namely Top, Right, Left, and Bottom. Each area can hold multiple stacked views. The visible part of an area is selected by a tab bar. The tab bars of the top and right area are at the top; the tab bars of the left and bottom area are at the bottom. You can specify which kind of view should go into which area by using the tabs' context menus.

### Synchronized View with Selected Entity in a Tab

Besides an active entity, each tab has a selected entity. As most view types show multiple entities with the active one somehow centered, you can change the selected item by navigating inside a view (by clicking with the mouse or using the keyboard). Typically, selected items are shown in a highlighted state. By changing the selected entity in one of the views of a tab, all other views highlight the new selected entity accordingly.

### Synchronization between Tabs

If there are multiple tabs, a selection change in one tab leads to an activation change in the next tab, be it right of the former or under it. This kind of linkage should, for example, allow for fast browsing in call graphs.

### Disposicións

The layout of all the tabs of a window can be saved (View → Layout). After duplicating the current layout (View → Layout → Duplicate (Ctrl++)) and changing some sizes or moving a view to another area of a tab, you can quickly switch between the old and the new layout via Ctrl+← and Ctrl+→. The set of layouts will be stored between KCachegrind sessions of the same profiled command. You can make the current set of layouts the default one for new KCachegrind sessions, or restore the default layout set.

Acoples laterais
Acoples laterais

## Acoples laterais

### Perfil simples

The Flat Profile contains a group list and a function list. The group list contains all groups where cost is spent in, depending on the chosen group type. The group list is hidden when grouping is switched off.

The function list contains the functions of the selected group (or all functions if grouping is switched off), ordered by some column, isto é inclusive or self costs spent therein. There is a maximum number of functions shown in the list, configurable in Settings → Configure KCachegrind.

### Resumo das Partes

In a profile run, multiple profile data files can be produced, which can be loaded together into KCachegrind. The Parts Overview sidedock shows these, ordered horizontally according to creation time; the rectangle sizes are proportional to the cost spent each part. You can select one or several parts to constrain the costs shown in the other KCachegrind views to these parts only.

The parts are further subdivided between a partitioning and an inclusive cost split mode:

Partitioning Mode

  The partitioning is shown in groups for a profile data part, according to the group type selected. For example, if ELF object groups are selected, you see colored rectangles for each used ELF object (shared library or executable), sized according to the cost spent therein.

Diagram Mode

  A rectangle showing the inclusive cost of the current active function in the part is shown. This, again, is split up to show the inclusive costs of its callees.

### Pila de Chamadas

This is a purely fictional « most probable » call stack. It is built up by starting with the current active function, and adds the callers and callees with highest cost at the top and to bottom.

The Cost and Calls columns show the cost used for all calls from the function in the line above.

Views
Views

## Views

### Event Type

The Event Type list shows all cost types available and the corresponding self and inclusive cost of the current active function for that event type.

By choosing an event type from the list, you change the type of costs shown all over KCachegrind to the selected one.

### Lista de chamadas

These lists show calls to and from the current active function. With All Callers and All Callees are meant those functions reachable in the caller and callee direction, even when other functions are in between.

As vistas de lista de chamadas inclúen:

- Direct Callers

- Direct Callees

- Todos os chamadores

- Todos os chamados

### Mapas

A treemap view of the primary event type, up or down the call hierarchy. Each colored rectangle represents a function; its size is approximately proportional to the cost spent therein while the active function is running (however, there are drawing constrains).

For the Caller Map, the graph shows the nested hierarchy of all callers of the currently activated function; for the Callee Map, it shows that of all callees.

Appearance options can be found in the context menu. To get exact size proportions, choose Skip Incorrect Borders. As this mode can be very time-consuming, you may want to limit the maximum drawn nesting level before. Best determinates the split direction for children from the aspect ratio of the parent. Always Best decides on remaining space for each sibling. Ignore Proportions takes space for function name drawing before drawing children. Note that size proportions can get heavily wrong.

Keyboard navigation is available with the left and right arrow keys for traversing siblings, and up and down arrow keys to go a nesting level up and down. Intro activates the current item.

### Grafo de chamadas

This view shows the call graph around the active function. The cost shown is only the cost spent while the active function was actually running, isto é the cost shown for `main()` (if it's visible) should be the same as the cost of the active function, as that is the part of inclusive cost of `main()` spent while the active function was running.

For cycles, blue call arrows indicate that this is an artificial call, which never actually happened, added for correct drawing.

If the graph is larger than the drawing area, a bird's eye view is shown on a side. There are view options similar to those of the call maps; the selected function is highlighted.

### Anotacións

The annotated source or assembler lists show the source lines or disassembled instructions of the current active function together with the (self) cost spent executing the code of a source line or instruction. If there was a call, lines with details on the call are inserted into the source: the (inclusive) cost spent inside of the call, the number of calls happening, and the call destination.

Escolla unha destas liñas de información de chamadas para activar o destino da chamada.

Capítulo 4. Referencia dos comandos
Referencia dos comandos

# Capítulo 4. Referencia dos comandos

## A fiestra principal de KCachegrind

### O menú Ficheiro

File → New (Ctrl+N)

  Opens an empty top-level window in which you can load profile data. This action is not really necessary, as File → Open gives you a new top-level window if the current one already shows some data.

File → Open (Ctrl+O)

  Pops up the KDE file selector to choose a profile data file to be loaded. If there is some data already shown in the current top-level window, this will open a new window; if you want to open additional profile data in the current window, use File → Add.

  The name of profile data files usually ends in `.`pid`.`part`-`threadID``, where `part` and `threadID` are optional. `pid` and `part` are used for multiple profile data files belonging to one application run. By loading a file ending only in ``pid``, any existing data files for this run with additional endings are loaded as well.

  If there exist profile data files `cachegrind.out.123` and `cachegrind.out.123.1`, by loading the first, the second will be automatically loaded too.

File → Add

  Adds a profile data file to the current window. Using this, you can force multiple data files to be loaded into the same top-level window even if they are not from the same run, as given by the profile data file naming convention. For example, this can be used for side-by-side comparison.

File → Reload (F5)

  Reload the profile data. This is useful when another profile data file was generated for an already loaded application run.

File → Quit (Ctrl+Q)

  Sai de KCachegrind

Capítulo 5. Preguntas e respostas
Preguntas e respostas

# Capítulo 5. Preguntas e respostas

Poida que este documento teña sido anovado desde que o instalou. Pode encontrar a última versión en http://docs.kde.org/current/kdesdk/.

5.1. Para que serve KCachegrind? .
5.2. What is the difference between Incl. and Self?
5.3. The toolbar and menubar of my KCachegrind look spartan. Is this normal?
5.4. If I double-click on a function down in the Call Graph view, it shows for function main() the same cost as the selected function. Isn't this supposed to be constant at 100%?

5.1. | Para que serve KCachegrind? .
| KCachegrind is a helpful at a late stage in software development, called profiling. If you don't develop applications, you don't need KCachegrind.
5.2. | What is the difference between Incl. and Self?

These are cost attributes for functions regarding some event type. As functions can call each other, it makes sense to distinguish the cost of the function itself (« Self Cost ») and the cost including all called functions (« Inclusive Cost »). « Self » is sometimes also referred to as « Exclusive » costs.

So, for example, for `main()`, you will always have an inclusive cost of almost 100%, whereas the self cost is negligible when the real work is done in another function.

5.3. | The toolbar and menubar of my KCachegrind look spartan. Is this normal?
| KCachegrind has probably been installed incorrectly on your system. It is recommended to compile it with the installation prefix set to your system-wide KDE base folder, like `configure `--prefix=`/opt/kde4``; make install`. If you choose another folder, like `$`HOME`/kde`, you should set the environment variable `KDEDIR` to this folder before running KCachegrind.
5.4. | If I double-click on a function down in the Call Graph view, it shows for function `main()` the same cost as the selected function. Isn't this supposed to be constant at 100%?
| You have activated a function below `main()`, which obviously costs less than `main()` itself. For every function, it is shown only the part of the cost spent while the activated function is running; that is, the cost shown for any function can never be higher than the cost of the activated function.

Glosario
Glosario

# Glosario

Cost Entity

  An abstract item related to source code to which event counts can be attributed. Dimensions for cost entities are code location (isto é source line, function), data location (isto é accessed data type, data object), execution location (isto é thread, process), and tuples or triples of the aforementioned positions (isto é calls, object access from statement, evicted data from cache).

Event Costs

  Sum of events of some event type occurring while the execution is related to some cost entity. The cost is attributed to the entity.

Event Type

  The kind of event of which costs can be attributed to a cost entity. There are real event types and inherited event types.

Inherited Event Type

  A virtual event type only visible in the view, defined by a formula to be calculated from real event types.

Profile Data File

  A file containing data measured in a profile experiment, or part of one, or produced by post-processing a trace. Its size is typically linear with the code size of the program.

Profile Data Part

  Data from a profile data file.

Profile Experiment

  A program run supervised by a profiling tool, producing possibly multiple profile data files from parts or threads of the run.

Profile Project

  A configuration for profile experiments used for one program to profile, perhaps in multiple versions. Comparisons of profile data typically only makes sense between profile data produced in experiments of one profile project.

Profiling

  The process of collecting statistical information about runtime characteristics of program runs.

Real Event Type

  An event type that can be measured by a tool. This requires the existence of a sensor for the given event type.

Trace

  A sequence of timestamped events that occurred while tracing a program run. Its size is typically linear with the execution time of the program run.

Trace Part

  Consulte Profile Data Part.

Tracing

  The process of supervising a program run and storing its events, sorted by a timestamp, in an output file, the trace.

Capítulo 6. Recoñecimentos e Licenza
Recoñecimentos e Licenza

# Capítulo 6. Recoñecimentos e Licenza

Grazas a Julian Seward polo seu excelente Valgrind e a Nicholas Nethercote pola adición de Cachegrind. Sen estes programas, KCachegrind non había existir. Asimesmo, algunhas ideas para esta GUI son deles.

Thanks for all the bug reports and suggestions from different users.

mvillarino`(mvillarino AT users.sourceforge.net)`

Esta documentación está licenciada sob os termos da GNU Free Documentation License.

Apêndice A. Instalación
Instalación

# Apêndice A. Instalación

## Como obter KCachegrind

KCachegrind is part of the kdesdk package of KDE. For less supported interim releases, Callgrind and further documentation, see the Web page. Look there for further installation and compile instructions.

Requerimentos
Requerimentos

## Requerimentos

In order to use KCachegrind, you need KDE 4.x. To generate profile data, Cachegrind or Calltree/Callgrind is recommended.

Compilación e Instalación
Compilación e Instalación

## Compilación e Instalación

Para poder compilar e instalar o KCachegrind no sistema, escreba os seguintes comandos no directorio raíz da distribución de KCachegrind:

    % ./configure
    % make
    % make install

Dado que KCachegrind emprega autoconf e automake non debera ter nengún problema a compilalo. Se o tiver, comuníqueo nas listas de KDE.

Configuración
Configuración

## Configuración

All configuration options are either in the configuration dialog or in the context menus of the views.