Re: Re: com php-src: Added an experemental ability to move PHP code pages (PHP TEXT segment) into HUGE pages. PHP should be configured and built with
--enable-huge-code-pages, OS should be configured to provide huge pages. It's possibl

On Mon, Sep 14, 2015 at 11:05 PM, Anatol Belski <anatol.php@belski.net> wrote: > Hi Dmitry, > > > -----Original Message----- > > From: Dmitry Stogov [mailto:dmitry@zend.com] > > Sent: Monday, September 14, 2015 12:58 PM > > To: Anatol Belski <ab@php.net>; Kalle Sommer Nielsen <kalle@php.net>; > > Rasmus Lerdorf <rasmus@lerdorf.com>; Xinchen Hui <xinchen.h@zend.com>; > > Nikita Popov <nikita.ppv@gmail.com>; Zeev Suraski <zeev@zend.com>; Andi > > Gutmans <andi@zend.com>; PHP Internals <internals@lists.php.net> > > Subject: [PHP-DEV] Re: [PHP-CVS] com php-src: Added an experemental > ability > > to move PHP code pages (PHP TEXT segment) into HUGE pages. PHP should be > > configured and built with --enable-huge-code-pages, OS should be > configured to > > provide huge pages. It's possible to > > > > The effect of this patch is really exiting to keep it disabled by > default... :) > > > > $ perf stat -e instructions,iTLB-loads,iTLB-load-misses,cycles > > sapi/cgi/php-cgi -d opcache.enable_huge_code_pages=0 -T 10000 > > /var/www/html/bench/wordpress-3.6/index.php > /dev/null > > > > 191,778,620,621 instructions # 0.81 insns per > > cycle > > 178,497,016 > > iTLB-loads > > 87,351,276 iTLB-load-misses # 48.94% of all iTLB > > cache hits > > 238,136,402,797 > > cycles > > > > 110.221114219 seconds time elapsed > > > > $ perf stat -e instructions,iTLB-loads,iTLB-load-misses,cycles > > sapi/cgi/php-cgi -d opcache.enable_huge_code_pages=1 -T 10000 > > /var/www/html/bench/wordpress-3.6/index.php > /dev/null > > > > 191,780,181,536 instructions # 0.83 insns per > > cycle > > 39,017,004 > > iTLB-loads > > 41,631,359 iTLB-load-misses # 106.70% of all iTLB > > cache hits > > 231,287,491,307 > > cycles > > > > 107.742837269 seconds time elapsed > > > > May be we should enable this by default in RC (may be also file cache) > and make > > decision based on feedback? > > > The file cache feature has proven itself as stable already, IMHO it should > be built by default in RC3. > OK. > > With the new huge memory pages feature I'd suggest a bit softer - enabling > its building, but setting opcache.enable_huge_code_pages=0 by default. OK. > Then it can be easy enable and give one more intermediate step for pre > testing and go into RC4 completely if ok. In general we may get build problems on some platforms... > What do you think? > I didn't get, do you like to delay this for RC4? or enable it at compile time and disable at run-time by default for RC3? I agree with both. Thanks. Dmitry. > > Regards > > Anatol > >