Google Performance Tools

Google Performance Tools (gperftools, formerly Google Performance Tools) is a collection of utilities for performance measurement and analysis of C and C++ programs, developed at Google and used extensively in Google's internal infrastructure. Key components include: TCMalloc (thread-caching memory allocator that provides faster allocation and deallocation than standard malloc by maintaining per-thread caches of free memory, reducing lock contention and improving cache locality for multi-threaded applications), Heap Profiler (heap sampling profiler that records memory allocation and deallocation events, generating heap profiles showing allocation sites, allocation sizes, and in-use memory by call stack, compatible with pprof visualization tool), CPU Profiler (sampling-based CPU profiler that periodically interrupts program execution to record call stacks, generating profiles showing function call frequency and time distribution without requiring recompilation), and TCMalloc Minimal (lightweight version including only the memory allocator without profiling overhead). Key features include: no source code modification (profilers can be linked at compile time or loaded dynamically at runtime via LD_PRELOAD), pprof integration (profiles are viewable as text, PDF, SVG call graphs, and interactive web UI via pprof tool), per-thread allocation tracking (TCMalloc maintains thread-local caches eliminating lock contention for small allocations), sized deallocation (C++14 sized delete support for faster deallocation), aggressive virtual memory management (uses madvise to return unused memory to the OS), configuration via environment variables (TCMALLOC_LARGE_ALLOC_REPORT_THRESHOLD, TCMALLOC_SAMPLE_PARAMETER, CPUPROFILE, HEAPPROFILE), and Linux/x86-64 focus (primary platform with some ARM support).