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1. AutoProfiling

By using eBPF to capture snapshots of application function call stacks, DeepFlow can generate Profiling flame graphs for any process, helping developers quickly identify function performance bottlenecks. In addition to business functions, the function call stack also displays the time consumption of dynamic link libraries, language runtimes, and kernel functions. Moreover, DeepFlow generates a unique identifier when collecting function call stacks, which can be used to correlate with call logs, enabling the integration of distributed tracing and function performance profiling.

DeepFlow's AutoProfiling

2. Capabilities and Limitations

Supported eBPF Profiling data types:

Type	Supported Languages/Libraries	Community Edition	Enterprise Edition
on-cpu	Java	✔	✔
	C/C++	✔	✔
	Rust	✔	✔
	Golang	✔	✔
	Python *	✔	✔
	CUDA *	✔	✔
	Lua *	✔	✔
off-cpu	Java		✔
	C/C++		✔
	Rust		✔
	Golang		✔
	Python *		✔
	CUDA *		✔
	Lua *		✔
mem-alloc	Java		✔
	Rust *		✔
	Golang *		✔
	Python *		✔
mem-inuse	Rust *		✔
hbm-alloc	Python *		✔
hbm-inuse	Python *		✔
rdma	C/C++ *		✔

Notes:

• *: features in development
• Types:
  • on-cpu: Time spent by functions on the CPU
  • off-cpu: Time functions wait for the CPU
  • mem-alloc: Total memory allocation of objects and function call stacks
  • mem-inuse: Current memory usage of objects and function call stacks
  • hbm-alloc: Total GPU memory allocation of objects and function call stacks
  • hbm-inuse: Current GPU memory usage of objects and function call stacks
• Languages:
  • Languages compiled into ELF format executables: Golang, Rust, C/C++
  • Languages using the JVM: Java

Two prerequisites must be met to obtain Profiling data:

• The process needs to enable Frame Pointer
  • Compiling C/C++: gcc -fno-omit-frame-pointer
  • Compiling Rust: RUSTFLAGS="-C force-frame-pointers=yes"
  • Compiling Golang: Enabled by default, no additional compilation parameters needed
  • Running Java: -XX:+PreserveFramePointer
• For processes of compiled languages, ensure to retain the symbol table during compilation

The Off-CPU Profiling feature only collects the following call stacks:

• Call stacks where the process state equals TASK_INTERRUPTIBLE (interruptible sleep) or TASK_UNINTERRUPTIBLE (uninterruptible sleep) when yielding the CPU
• Call stacks excluding the 0th process (Idle process)
• Call stacks containing at least one user-mode function
• Call stacks where the CPU wait time does not exceed 1 hour