How to trace or debug slab leaks

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  • Red Hat Enterprise Linux


  • How do I trace allocation of slabs?
  • Slab memory usage is quite high. How do I determine who is generating the slab allocations?


Quite a few options exist to trace slab allocations.


Systemtap (also known as stap) provides a method for writing scripts to perform debugging and tracing activity in the kernel, compile the script into a custom kernel module, and load the module to enable the troubleshooting functionality provided by the custom script.


Perf is a userspace tool which interacts with the ftrace subsystem of the kernel to perform tracing within kernelspace execution.


Extended Berkeley Packet Filter (eBPF) enables tracing and debugging within a sandboxed, in-kernel virtual machine. Tracing and debugging is written out similar to Clang programs and compiled via the BPF Compiler Collection (BCC).

Tooling within the kernel

The linux kernel offers the slub_debug kernel parameter (as well as sysfs files) to enable debugging options for slab.

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