How to Inspect Go Program Memory with Delve: A Step‑by‑Step Guide

What is Delve

Delve is a Go debugging tool that provides breakpoint debugging, data inspection, and the ability to switch between goroutines. Most IDEs already integrate it.

Program Memory Overview

When a Go program runs, its binary is loaded into memory, consisting of code, stack, and heap. The stack grows downward, the heap upward, but Go's runtime and goroutine scheduling can affect actual address layout. Byte order on typical x86/AMD CPUs is little‑endian, meaning the least‑significant byte is stored at the lowest address.

Example: a pointer value 0xc0123456 is stored as 0x56 0x34 0x12 0xc0 (on a 32‑bit illustration; on 64‑bit it occupies eight bytes).

Using Delve for Memory Inspection

After installing Delve, start debugging the main file: dlv debug main.go Set a breakpoint at line 9: b main.go:9 Run the program until the breakpoint, then view the disassembly of the current address:

disass -a 0x495c75 0x495d75

Inspect variable values:

p a

p b

To view raw memory at a specific address in hexadecimal format, use:

x -fmt hex -len 32 0xc00010cef0

The output shows 8‑byte rows; the first eight bytes after the address of variable a contain the integer value 1, confirming the stored data.

Repeating the process for variable b reveals its address, length, and the underlying bytes. The first eight bytes represent the address of the string data, followed by three bytes that correspond to the ASCII characters “abc”. The subsequent bytes represent the string length (3), matching Go’s string representation as a pointer plus length.

Summary

This example demonstrates Delve’s memory‑view capabilities, helping developers understand Go’s data layout, string representation, and the impact of memory allocation on performance. It also highlights why naïvely appending to a string can trigger additional heap allocations and garbage‑collection cycles.