Re: [PATCH/22885] Detect altered malloc chunks

[DJ Delorie <dj at redhat dot com>]

"Carlos O'Donell" <carlos@redhat.com> writes:
> Are you available to run this patch through a performance test with
> the simulator and workloads? All the changes are fairly light weight
> and touching data we likely already have hot in the cache, and they
> are mostly mask/test operations. I don't expect them to have a visible
> impact.

I combined Mike's patch with Florian's two (no strict aliasing,
accessors - the fastbin one was already committed), Adam's, and mine,
and benchmarked them all together.  I ran each workload through the
simulator 16 times and averaged the results, for each of four workloads,
against both pristine and patched sources.  Results below.  Deviations
are within 1% but no specific trend.

dj@envy pts/27 ~/tools
$ go oocalc okular-1 fluentd 389ds

----------  oocalc ----------

PRISTINE:
Total call time: 1,073,761,546 cycles

PATCHED: 
Total call time: 1,079,895,621 cycles

----------  okular-1 ----------

PRISTINE:
Total call time: 3,271,045,477 cycles

PATCHED: 
Total call time: 3,258,433,903 cycles

----------  fluentd ----------

PRISTINE:
Total call time: 6,317,728,016 cycles

PATCHED: 
Total call time: 6,266,545,907 cycles

----------  389ds ----------

PRISTINE:
Total call time: 7,613,754,098 cycles

PATCHED: 
Total call time: 7,564,173,273 cycles