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| | == Multi-core debugging use cases == | | == Multi-core debugging use cases == |
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| − | * '''1) Programs with multiple threads'''
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| − | *:1.1) Two or more threads interacting : User is debugging a program with multiple threads which are interacting with each other.
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| − | *::1.1.1) Debugging threads which contend for the same lock. :
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| − | *::# When a thread blocks while stepping,
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| − | *::# User switches focus to another thread and steps until the lock is released,
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| − | *::# User switches focus back to the first thread and continues debugging.
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| − | *::1.1.2) Debugging race conditions where multiple threads are reading and writing some shared data :
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| − | *::# User sets a breakpoint at a location where a shared variable is written.
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| − | *::# Multiple threads hit the breakpoint
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| − | *::# User looks at each threads to see the thread-private data in each thread.
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| − | *::# User steps the threads individually to watch what happens to the shared data.
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| − | *::# Alternatively, user steps all threads.
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| − | *::# Multiple threads may hit the breakpoint at the same time.
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| − | *::# User sets another breakpoint further down in routines that access the shared data.
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| − | *::# Halt execution when another thread accesses shared address.
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| − | *::# User continues some or all of the threads which stopped at the first breakpoint so that they may reach the second breakpoint.
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| − | *:1.2) Debugging a subset of threads : User is debugging a program with multiple threads, but he is interested only in interacting with some of the threads.
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| − | *::1.2.1) User debugs with breakpoints restricted to a sub-set of threads.
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| − | *::# User creates a breakpoint on the routine to be debugged.
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| − | *::# User defines which threads should be allowed to hit the breakpoint.
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| − | *::# The threads hit the breakpoint and user steps through them.
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| − | *::1.2.2) Run control for a subset of threads : User repeatedly suspends and resumes a subset of threads.
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| − | *::1.2.3) Terminating/re-launching :
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| − | *::# User debugs a subset of threads (using filtered breakpoints, etc.).
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| − | *::# User terminates and relaunches a process, and continues to debug the same set of threads.
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| − | *::1.2.4) Tasks submitted to a thread pool : User is debugging a routine which may be executed by any thread in a thread pool at any time, and by some threads in the thread pool at the same time.
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| − | *::# User sets a breakpoint and a number of threads hit the breakpoint, user examines the data and resumes threads individually.
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| − | *::# User sets a conditional breakpoint where the condition is used to identify a specific tasks. For example, an instance of an update object when debugging flexible hierarchy views.
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| − | *:1.3) Program with large number (100+) of threads : User is debugging programs with large numbers of threads and he needs to manage those threads effectively.
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| − | *::1.3.1) User needs to switch between suspended threads
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| − | *::# User sets a breakpoint that some threads may hit.
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| − | *::# Some threads hit the breakpoint.
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| − | *::# User switches focus between suspended threads to control them and examine their data.
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| − | *::1.3.2) Threads created/destroyed rapidly: User is debugging a process with threads being created and destroyed at a rapid rate (more than 1 thread/sec.)
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| − | *:1.4) Context-specific expressions : User is using the expressions view to monitor different expressions which are valid only in specific context.
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| − | *::1.4.1) Local variable expressions : User creates expressions for local variables in a specific function. These variables are not valid in any other context.
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| − | *::1.4.2) Thread-local variable expressions : User creates expressions for variables which are valid only in specific threads.
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| − | *:1.5) Clone threads : Debugging a system where multiple threads are executing the same section of code.
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| − | *::1.5.1) Comparing data in clone threads : User compares variables in threads which are stopped in the same section of code.
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| | * '''3) Systems with multiple cores (On Chip Debugging)''' | | * '''3) Systems with multiple cores (On Chip Debugging)''' |
| | *:3.1) Hardware bring-up debugging : User attaches a debugger to a multi-core system for purpose of hardware configuration, such as configuring registers, IO devices, etc. (no OS, no symbol data, no executable image) | | *:3.1) Hardware bring-up debugging : User attaches a debugger to a multi-core system for purpose of hardware configuration, such as configuring registers, IO devices, etc. (no OS, no symbol data, no executable image) |
| | *:3.2) No-OS debugging : User attaches to a multi-core system and downloads simple executable image to each core and debugs them. | | *:3.2) No-OS debugging : User attaches to a multi-core system and downloads simple executable image to each core and debugs them. |
