Re: [PATCH v3 31/35] lib: add memory allocations report in show_mem()

From: Steven Rostedt
Date: Thu Feb 15 2024 - 18:20:20 EST


On Thu, 15 Feb 2024 18:07:42 -0500
Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:

> text data bss dec hex filename
> 29161847 18352730 5619716 53134293 32ac3d5 vmlinux.orig
> 29162286 18382638 5595140 53140064 32ada60 vmlinux.memtag-off (+5771)
> 29230868 18887662 5275652 53394182 32ebb06 vmlinux.memtag (+259889)
> 29230746 18887662 5275652 53394060 32eba8c vmlinux.memtag-default-on (+259767) dropped?
> 29276214 18946374 5177348 53399936 32ed180 vmlinux.memtag-debug (+265643)

If you plan on running this in production, and this increases the size of
the text by 68k, have you measured the I$ pressure that this may induce?
That is, what is the full overhead of having this enabled, as it could
cause more instruction cache misses?

I wonder if there has been measurements of it off. That is, having this
configured in but default off still increases the text size by 68k. That
can't be good on the instruction cache.

-- Steve