Re: [RFC] scripts: Include postprocessing script for memory allocation tracing

[Janani Ravichandran <janani.rvchndrn@xxxxxxxxx>]

On Oct 17, 2016, at 1:24 PM, Janani Ravichandran <janani.rvchndrn@xxxxxxxxx> wrote:

On Sun, Oct 16, 2016 at 3:33 AM, Michal Hocko <mhocko@xxxxxxxxxx> wrote:

trace_mm_page_alloc will tell you details about the allocation, like
gfp mask, order but it doesn't tell you how long the allocation took at
its current form. So either you have to note jiffies at the allocation
start and then add the end-start in the trace point or we really need
another trace point to note the start. The later has an advantage that
we do not add unnecessary load for jiffies when the tracepoint is
disabled.

The function graph tracer can tell us how long alloc_pages_nodemask() took.

Can’t that, combined with the context information given by trace_mm_page_alloc

give us what we want? Correct me if I am wrong.

Regards,

Janani.

--
Michal Hocko
SUSE Labs