Software Linux Reviews & Articles

There have been 904 Linux hardware reviews and benchmark articles on Phoronix for software. Separately, check out our news section for related product news.

At the start of the month AMD released AOCC 2.3 as the newest version of the AMD Optimizing C/C++ Compiler. AOCC is one of several LLVM/Clang downstream versions maintained by the company with this one being about delivering flagship AMD Zen family compiler support. From an AMD EPYC 7002 "Rome" series processor I recently wrapped up fresh benchmarks of AOCC 2.3 against the current GCC 10 and Clang 11 compiler releases.

Last week AMD published their Zen 3 support for GCC code compiler. That initial support, which has already been merged into GCC 11, is the initial support flipping on newly supported instructions but not yet offering any tuned scheduler model or other optimizations compared to the existing Zen 2 path. In any case, here is a look at the performance changes with building the open-source benchmarks under test with "znver3" compared to the prior Zen 2 and Zen 1 targets along with generic x86_64 and then also looking at the performance if catering the compiler targets for Intel's Skylake and Haswell processors.

Last week I provided some benchmarks looking at the IBM POWER9 mitigation for the L1 data cache needing to be flushed upon entering the kernel and on user accesses due to a recently disclosed vulnerability. POWER9 allows speculatively operating on validated data in the L1 cache, but when it comes to incompletely validated data paired with other side channels it could lead to local users potentially obtaining improper access to data in the L1 data cache. When benchmarking the impact on a POWER9 4c/16t CPU the overall impact was fairly modest while since then I fired up some benchmarks as well on a large POWER9 server with 44 cores / 176 threads to see the performance impact of this default Linux kernel change.

With this month's release of Chrome 87 having more performance improvements while Firefox 83 debuted with its "Warp" JavaScript improvements, it's a good time for some fresh Linux web browser benchmarks of these two main options. Plus with Firefox 84 to begin enabling WebRender by default in some Linux configurations, there is also a fresh run of Firefox with WebRender enabled.

One area not talked about much for Intel's latest Tiger Lake processors are hardened CPU security mitigations against the various speculative execution vulnerabilities to date. What's peculiar about Tiger Lake though is now if disabling the configurable mitigations it can actually result in worse performance than the default mitigated state. At least that's what we are seeing so far with the Core i7 1165G7 on Ubuntu 20.10 Linux is the opposite of what we have been seeing on prior generations of hardware.

Last week a new vulnerability was made public for IBM POWER9 processors resulting in a mitigation of the processor's L1 data cache needing to be flushed between privilege boundaries. Due to the possibility of local users being able to obtain data from the L1 cache improperly when this CVE is paired with other side channels, the Linux kernel for POWER9 hardware is flushing the L1d on entering the kernel and on user accesses. Here are some preliminary benchmarks looking at how this security change impacts the overall system performance.

Now that the Samsung-contributed open-source exFAT file-system kernel driver has matured quite nicely since being merged earlier this year as a replacement to the short-lived staging exFAT driver based on an older code-base, here is a look at how exFAT is performing on the Linux 5.9 kernel compared to EXT4 and F2FS as well as the existing exFAT FUSE file-system implementation.

Making use of "-march=tigerlake" for building optimized binaries catering to Intel's latest-generation processors is well worth it on the likes of GCC 11. Out of the new instruction set extensions on Tiger Lake is more uplift than we have seen out of recent Intel generations and comparing the different "-march=" targets shows significant performance benefits if you don't mind compiling your own software from source.

The Linux 5.10 merge window is set to close this afternoon followed by around seven weeks worth of release candidates before the stable kernel release in December. As usual here is our look at the many new features set to premiere with this next version of the Linux kernel.

With Ubuntu 20.10 due for release this week I have begun testing near-final Ubuntu 20.10 builds on many more systems in the lab. Larger than our normal distribution/OS comparisons, here is the culmination of running hundreds of benchmarks (366 tests to be exact) under both Ubuntu 20.04 LTS with all available updates and then again on the Ubuntu 20.10 development state while testing on Intel Comet Lake.

Phoronix Test Suite 10.0-Finnsnes is now officially available as the latest major feature release for our open-source, cross-platform automated benchmarking software that now has more than six hundred tests/benchmarks available for fully-automated testing. With Phoronix Test Suite 10.0 also comes a significant overhaul to OpenBenchmarking.org and its biggest since its debut back in 2011 alongside Phoronix Test Suite 3.0.

Of the many new features in Linux 5.9 with its debut set for this weekend, one of the performance-related changes is Intel FSGSBASE support finally being mainlined. A half-decade after the Linux patches first appeared for this feature present in Intel CPUs going back to Ivy Bridge, the mainline kernel is now patched for this feature that can help out I/O and other context switching heavy workloads. Given many of the same workloads were negatively impacted by the CPU security mitigations of recent years, here is a look at the current mitigated vs. unmitigated performance difference on the Linux 5.9 kernel with an Intel Core i9 9900K CPU for reference on how the mitigation impact is on recent versions of the Linux kernel.

Following last week's news of Firefox Nightly flipping on their new JIT "Warp" update I was eager to run fresh benchmarks of the current Firefox releases compared to Google Chrome under Ubuntu Linux.

After announcing oneAPI at the end of 2018 and then going into beta last year, oneAPI 1.0 is now official for this open-source, standards-based unified programming model designed to support Intel's range of hardware from CPUs to GPUs to other accelerators like FPGAs. Intel's oneAPI initiative has been one of several exciting software efforts led by the company in recent years while continuing to serve as one of the world's largest contributors to open-source software.

One of the most frequent questions received at Phoronix in recent times is whether the "schedutil" governor is ready for widespread use and if it can compare in performance to, well, the "performance" governor on AMD Linux systems. Here are some benchmarks of an AMD Ryzen 9 3900XT using the latest Linux 5.9 development kernel in looking at the performance differences between the CPUFreq governor options of Ondemand, Powersave, Performance, and Schedutil.

Following the Linux 5.0 to 5.9 kernel benchmarks on AMD EPYC and it showing the in-development Linux 5.9 kernel regressing in some workloads, bisecting that issue, and that bringing up the issue of the performance regression over page lock fairness a solution for Linux 5.9 has now landed.

Last week we reported on a Linux 5.9 kernel regression following benchmarks from Linux 5.0 to 5.9 and there being a sharp drop with the latest development kernel. That kernel regression was bisected to code introduced by Linus Torvalds at the start of the Linux 5.9 kernel cycle. Unfortunately it's not a trivial problem and one still being analyzed in coming up with a proper solution. So the short story is it's a work-in-progress while this article has some additional insight and benchmarks done over the course of the past few days.

The Linux 5.0 to 5.9 kernel benchmarking posted this week showed TensorFlow Lite running slower since the Linux 5.5 kernel... On top of looking at the new Linux 5.9 regressions, I also spent some time bisecting and figuring out what happened for TensorFlow Lite last year that has at least for the system under test caused it to run slower for all the kernel releases this year as shown in the aforelinked article.

Recently carrying out some benchmarks of all major kernel releases from Linux 5.0 through Linux 5.9 ended up yielding some surprising performance changes with the in-development 5.9 kernel. Here's details on this historical look at the kernel performance and what's going on with the Linux 5.9 kernel slowdowns.

Following the debut of the big Blender 2.90 release and subsequently updating it for the Phoronix Test Suite / OpenBenchmarking.org, here is a deep dive into the Blender 2.90 performance... A number of areas are being looked at with the initial Blender 2.90 benchmarks from how the performance is on various CPUs and GPUs to the performance of the Blender 2.82 vs. 2.90 to looking at the Windows vs. Linux performance for Blender 2.90 with various means of acceleration.

At the end of June AMD quietly released a new version of the AMD Optimizing C/C++ Compiler. Noticing the new release this week, here are some benchmarks of AOCC 2.2 up against LLVM Clang 10 and GCC 10 with Ubuntu Linux while running from an AMD EPYC 7742 2P server for looking at the performance gains possible with the compiler optimizations.

As alluded to previously, a major overhaul of OpenBenchmarking.org has been in the works for a number of months now including a completely brand new analytics engine as part of the Phoronix Test Suite 10.0 development with its release due out later this year. With the new OpenBenchmarking.org now in good enough shape at least for the internal infrastructure, this new version is being opened up to the public today while over the weeks ahead more features will continue to be flipped on.

Linux 5.9-rc1 is set to be released this evening in marking the end of the two-week long merge window where new features are introduced for the cycle.

The FSGSBASE support that was finally mainlined a few days ago for Linux 5.9 is off to providing a nice performance boost for both Intel and AMD systems. Looking at FSGSBASE is one of the first areas I've dived into for Linux 5.9 kernel testing with this article serving as some preview/teaser data points.

With the Intel Core i9 10900K "Comet Lake" processor here are some fresh GCC compiler benchmarks when looking at the performance of GCC 8.4 versus 9.3 versus a 10.2 snapshot while testing with optimization flags of -O2, -O3 -march=native, and -O3 -march=native -flto.

Phoronix Test Suite 9.8 is available today as the latest quarterly stable feature release to our open-source, cross-platform benchmarking software.

Back in March I benchmarked the Linux Kernel Runtime Guard (LKRG) as a means of achieving additional security safeguards for a ~5% performance hit. With LKRG 0.8 having been released a few days ago, here is a fresh look at the LKRG performance compared to the stock kernel on Ubuntu 20.04 LTS.

One of the security improvements being worked on in recent months by Intel's open-source team has been FGKASLR. But how is the performance overhead compared to just traditional KASLR? Here are benchmarks looking at the performance impact of FGKASLR on top, just KASLR, and then no address space layout randomization.

Slated for Linux 5.9 is finally mainlining the FSGSBASE patches that have been floating around the kernel mailing list for years. Testing last week showed the tentative x86/fsgsbase patches helping Intel Xeon Linux performance but with AMD also supporting this instruction set extension going back to Bulldozer, how is it looking on the likes of AMD? Here are some benchmarks.

After covering the Linux patches for FSGSBASE for years, it's looking like Linux 5.9 will finally land the support for this CPU capability present since Ivy Bridge on the Intel side and more recently on AMD CPUs with Bulldozer and Zen. Here are benchmarks looking at some of the performance benefits the Linux FSGSBASE patches can provide for an Intel Xeon Cascade Lake Refresh server.