Re: [PATCH 00/11] Use global pages with PTI

Dave Hansen
2018-03-30T20:26:18Z

On 03/30/2018 05:17 AM, Ingo Molnar wrote:
> BTW., the expectation on !PCID Intel hardware would be for global pages to help
> even more than the 0.6% and 1.7% you measured on PCID hardware: PCID already
> _reduces_ the cost of TLB flushes - so if there's not even PCID then global pages
> should help even more.
>
> In theory at least. Would still be nice to measure it.

I did the lseek test on a modern, non-PCID system:

No Global pages (baseline): 6077741 lseeks/sec
94 Global pages (this set): 8433111 lseeks/sec
+2355370 lseeks/sec (+38.8%)