Next-Generation PHP 7.0 Is Running Well But Will It Catch Up To HHVM?

It's been a while since I've last tried out the Git code for the next-generation PHP (phpng) that's going to be known as PHP 7.0 when released likely later this year.

The next major release of PHP is to be called PHP7 in order to avoid confusion with the now-defunct PHP6 unicode initiative. PHP 7.0 is likely to be released by the end of 2015 per the PHP7 timeline. If the release candidates begin on time starting in June, we could be looking at the official PHP 7.0 release around October of this year. However, it's largely dependent upon the state of affairs at that point with the quality of the code.

The biggest feature of PHP 7 is the performance improvements due to major work on its Zend Engine, which will be Zend Engine 3 with PHP 7. Thanks to the competition from Facebook's HHVM, PHP.net has needed to step up their speed game big time, which they're managing to achieve with PHP 7.0.

Atop an Ubuntu 14.10 installation with Core i7 5960X Haswell-E processor, I was running some tests of PHP 7.0 mainline Git as of today compared to PHP 5.5 as packaged on Ubuntu 14.10, a built-from-source PHP 5.6.4, and HHVM 3.6.99. The tests were obviously with Phoromatic and the Phoronix Test Suite.

I don't have any huge and exciting PHP benchmark comparison to share today as will hold off until PHP 7.0 is actually closer to being released, but did run some basic phoronix-test-suite debug-self-test runs on each PHP release to see how the timings are. This Phoronix Test Suite sub-command just stresses a lot of the hot paths for the Phoronix Test Suite. Most of the work comes down to file operations, tons of math, XML parsing, and just other common PHP code all run from the phoronix-test-suite, a PHP CLI application run without a web server.

I was running the Phoronix Test Suite performance self-test on v5.4.1-Lipki. First up were the numbers with Ubuntu Utopic's 5.5.12 package:

PHP:  5.5.12-2ubuntu4.1
DETAILED_SYSTEM_INFO:          0.151 seconds
LIST_AVAILABLE_TESTS:          0.478 seconds
LIST_AVAILABLE_SUITES:         25.188 seconds
INFO:                          0.009 seconds
CLONE_OPENBENCHMARKING_RESULT: 46.081 seconds
RESULT_FILE_TO_TEXT:           4.947 seconds
DIAGNOSTICS:                   0.014 seconds
DUMP_POSSIBLE_OPTIONS:         0.001 seconds

ELAPSED TIME:                  230.607 seconds
PEAK MEMORY USAGE:             35.75 MB
PEAK MEMORY USAGE (emalloc):   34.213 MB

The test took 230.6 seconds with peak memory usage at around 35MB. Next up was PHP 5.6.4 built from source.

PHP:  5.6.4
DETAILED_SYSTEM_INFO:          0.147 seconds
LIST_AVAILABLE_TESTS:          0.347 seconds
LIST_AVAILABLE_SUITES:         18.021 seconds
INFO:                          0.007 seconds
CLONE_OPENBENCHMARKING_RESULT: 38.398 seconds
RESULT_FILE_TO_TEXT:           4.660 seconds
DIAGNOSTICS:                   0.014 seconds
DUMP_POSSIBLE_OPTIONS:         0.001 seconds

ELAPSED TIME:                  184.783 seconds
PEAK MEMORY USAGE:             35.75 MB
PEAK MEMORY USAGE (emalloc):   34.206 MB

PHP 5.6 was much faster with taking just 184 seconds in comparison to PHP 5.5's 230 seconds. The peak memory usage was around the same at 35MB for the self-test. Next is the look at PHP mainline Git as of this morning and built in the same manner as PHP 5.6.4.

PHP:  7.0.0-dev
DETAILED_SYSTEM_INFO:          0.138 seconds
LIST_AVAILABLE_TESTS:          0.252 seconds
LIST_AVAILABLE_SUITES:         12.408 seconds
INFO:                          0.005 seconds
CLONE_OPENBENCHMARKING_RESULT: 37.730 seconds
RESULT_FILE_TO_TEXT:           4.401 seconds
DIAGNOSTICS:                   0.011 seconds
DUMP_POSSIBLE_OPTIONS:         0.003 seconds

ELAPSED TIME:                  164.844 seconds
PEAK MEMORY USAGE:             30.879 MB
PEAK MEMORY USAGE (emalloc):   23.944 MB

With PHP 7.0 Git in its current development form, the self-test time drops another 20 seconds down to 164 seconds... Or around 30% compared to PHP 5.5 on Ubuntu 14.10. The peak memory usage is also measurably lower.

However, if looking at HHVM 5.6.99, the PHP 7.0 state for this particular test run doesn't look as appealing:

PHP:  5.6.99-hhvm
DETAILED_SYSTEM_INFO:          0.336 seconds
LIST_AVAILABLE_TESTS:          0.251 seconds
LIST_AVAILABLE_SUITES:         13.059 seconds
INFO:                          0.033 seconds
CLONE_OPENBENCHMARKING_RESULT: 14.521 seconds
RESULT_FILE_TO_TEXT:           0.014 seconds
DIAGNOSTICS:                   0.033 seconds
DUMP_POSSIBLE_OPTIONS:         0.004 seconds

ELAPSED TIME:                  84.759 seconds
PEAK MEMORY USAGE:             134.844 MB
PEAK MEMORY USAGE (emalloc):   14 MB

HHVM on the same Ubuntu Linux system was running the self-test in about half the time of PHP 7.0 Git. With a big difference in the clone OpenBenchmarking.org micro-test, it looks like HHVM's networking support might be running a heck of a lot faster than PHP, to at least partially explain some of the speed difference.

PHP 7.0 is making many improvements to its engine for greater performance, but it seems at least for this isolated test that Facebook's HipHop Virtual Machine is still dominating. Aside from the performance, PHP 7.0-devel Git was running well on the system with the few hours I've been using it to verify no issues against the newest Phoronix Test Suite / OpenBenchmarking.org / Phoromatic code.

Again, I'll be back with many more thorough PHP benchmarks and PHP 7.0 news as its release nears -- hopefully by the end of 2015! In the mean time, share your PHP 7 hopes and thoughts by commenting on this article.