elf-limits

Utility program that can be used to get an idea of the resource usage of ELFs loaded in memory.

This is done by looking at the memsz of segments in an ELF and printing out the numbers in a human readable form.

This program is most useful when your ELF is "self-contained", like in a lot of embedded settings. That means all memory that will ever be needed is accounted for in the ELF.

Because this program was written for embedded use cases, there are a few things to consider:

• Only R,R|W,R|X and loadable segments are taken into consideration
• If there are .stack and .heap ELF sections present, those will be counted as "dynamic" memory, as those usually grow dynamically or are dynamically used

Installation

cargo install --git https://github.com/cuddlefishie/elf-limits

Options

There are a few command line options:

• --fixed-only

  Only show fixed sizes (useful for resource estimation, because stack and heap can be configured)

• --total-mem-limit <TOTAL_MEM_LIMIT>

  Limit for total memory usage (respects --fixed-only)

• --data-mem-limit <DATA_MEM_LIMIT>

  Limit for data memory usage (respects --fixed-only)

• --instruction-mem-limit <INSTRUCTION_MEM_LIMIT>

  Limit for instruction memory usage

If any of the *-limit options is used, the program will also report if any of the ELFs use more resources. This will be reported both on stdout and in the return code of the program.

Example output

> elf-limits hello
File: hello
  Instruction memory:   5.31 KiB
  Data memory:            64 KiB
    Fixed:               428   B
    Stack:             63.58 KiB
  Total memory:        69.31 KiB
    Fixed:              5.73 KiB
    Dynamic:           63.58 KiB

> elf-limits --fixed-only hello
File: hello
  Instruction memory:   5.31 KiB
  Data memory fixed:     428   B
  Total memory fixed:   5.73 KiB

> elf-limits --fixed-only --total-mem-limit 128K --data-mem-limit 64K --instruction-mem-limit 64K hello
File: hello
  Instruction memory:   5.31 KiB (  8%)
  Data memory fixed:     428   B (  0%)
  Total memory fixed:   5.73 KiB (  4%)

> elf-limits --total-mem-limit 128K --data-mem-limit 64K --instruction-mem-limit 64K hello
File: hello
  Instruction memory:   5.31 KiB (  8%)
  Data memory:            64 KiB (100%)
    Fixed:               428   B (  0%)
    Stack:             63.58 KiB
  Total memory:        69.31 KiB ( 54%)
    Fixed:              5.73 KiB (  4%)
    Dynamic:           63.58 KiB

License

This project is licensed under the Apache 2.0 license.