Software Archives
An Early Look At The L1 Terminal Fault "L1TF" Performance Impact On Virtual Machines

Yesterday the latest speculative execution vulnerability was disclosed that was akin to Meltdown and is dubbed the L1 Terminal Fault, or "L1TF" for short. Here are some very early benchmarks of the performance impact of the L1TF mitigation on the Linux virtual machine performance when testing the various levels of mitigation as well as the unpatched system performance prior to this vulnerability coming to light.

15 August 2018 - 12 Comments
SIGGRAPH 2018: OpenCL-Next Taking Shape, Vulkan Continues Evolving

It's a busy week folks as besides the AMD Threadripper 2 performance embargo expiring, it is also SIGGRAPH 2018 week in Vancouver and as well the start of the Linux 4.19 kernel cycle... No longer under wraps are the Khronos announcements from this annual graphics conference. Continue reading to learn about the latest happenings for the various Khronos industry-standard APIs and efforts like Vulkan and OpenCL-Next.

13 August 2018 - 6 Comments
GCC 8/9 vs. LLVM Clang 6/7 Compiler Benchmarks On AMD EPYC

Following the GCC 9.0 benchmarks earlier this week I ran some tests seeing how the GCC 8 stable compiler and GCC 9 development state compare to the LLVM Clang 6.0.1 stable compiler and LLVM Clang 7.0 development. Here are those benchmarks using the AMD EPYC 7601 32-core / 64-thread processor.

27 July 2018 - 10 Comments
32-Bit Linux Prepares For Performance Hit Due To KPTI For Meltdown Mitigation

Since January there has been KPTI in the x86_64 Linux kernel as Kernel-based Page Table Isolation for mitigating the Meltdown CPU vulnerability. On the back-burner since then has been KPTI support for the Linux x86 32-bit kernel to protect those using older 32-bit-only processors. With the upcoming Linux 4.19 kernel, KPTI is landing for Linux x86 32-bit. Here are sone benchmarks showing the performance penalty when upgrading to this new kernel on an Ubuntu i686 laptop.

25 July 2018 - 10 Comments
An Early Look At The GCC 9.0 Performance On AMD EPYC

While GCC 9 has just been under development for a relatively short period of time, here are our initial benchmarks of GCC 9.0 SVN on and AMD EPYC server compared to the GCC 8.2 stable release candidate when tested at various optimization levels as well as PGO (Profile Guided Optimizations).

24 July 2018 - 4 Comments
A Fresh Look At The PGO Performance With GCC 8

It's been a while since we last ran some GCC PGO benchmarks, the Profile Guided Optimizations or feedback-directed optimization technique that makes use of profiling data at run-time to improve performance of re-compiled binaries. Here are some fresh benchmarks of GCC PGO impact on a Xeon Scalable server while using the newly-released GCC 8.2 release candidate.

19 July 2018 - 18 Comments
Benchmarking The Performance Impact Of Speculative Store Bypass Disable For Spectre V4 On Intel Core i7

In late May Spectre V4 was made public and coinciding with the public reveal was the Linux kernel patches for the Speculative Store Bypass Disable (SSBD) mode for mitigating this latest side-channel attack. For SSBD on Intel CPUs, updated microcode is required and those patched microcode files are now being delivered down through new BIOS updates from motherboard vendors. In recent days with seeing ASUS motherboards get the updated supported, I decided to run some initial Core i7 Coffeelake benchmarks with/without the SSBD support being enabled in the Linux kernel.

3 July 2018 - 6 Comments
Using W10Privacy To Boost Ubuntu WSL Performance On Windows 10

While Microsoft is working on low-level improvement to the Windows Subsystem for Linux (WSL) to yield better I/O performance, it is possible to dramatically increase some disk workloads by removing a number of running Windows services via the independent W10Privacy application. Here are some benchmarks of W10Privacy on the overall performance impact to Microsoft Windows 10 Pro x64 itself and of Ubuntu 18.04 running on the Windows 10 installation via WSL.

18 June 2018 - 25 Comments
The Changes & New Features For Linux 4.18

With the early release of Linux 4.18-rc1, feature development on Linux 4.18 is over and it's onto roughly eight weeks worth of testing and bug fixes. For those that are behind in their Phoronix reading with our extensive and original reporting on the Linux 4.18 merge window happenings, here is our recap of the big changes that made it into Linux 4.18. We are also in the process of firing off the start of our Linux 4.18 kernel benchmarks.

16 June 2018 - 5 Comments
Phoronix Test Suite 8.0 Debuts With Official Windows Support, Easier Benchmark Creation

Phoronix Test Suite 8.0 has premiered today as the latest quarterly update to our open-source, cross-platform automated benchmarking software. This also happens to be our largest release ever and also commemorates ten years since the release of Phoronix Test Suite 1.0 and fourteen-years since the start of Phoronix. Here is a look at some of the many enhancements to find in this open-source benchmarking software.

5 June 2018 - 4 Comments
GCC vs. LLVM Clang vs. AOCC Compilers On AMD Threadripper

Given recent improvements to AMD Zen (znver1) with LLVM, the new AMD AOCC 1.2 compiler release, and GCC 8.1 having premiered just weeks ago, here is a fresh look at the performance of six different C/C++ code compilers when testing the performance of the resulting binaries on an AMD Threadripper 1950X system.

23 May 2018 - 15 Comments
AMD AOCC 1.2 Code Compiler Offers Some Performance Benefits For EPYC

Last month AMD released the AOCC 1.2 compiler for Zen systems. This updated version of their branched LLVM/Clang compiler with extra patches/optimizations for Zen CPUs was re-based to the LLVM/Clang 6.0 code-base while also adding in experimental FLANG support for Fortran compilation and various other unlisted changes to their "znver1" patch-set. Here's a look at how the performance compares with AOCC 1.2 to LLVM Clang 6.0 and GCC 7/8 C/C++ compilers.

20 May 2018 - 5 Comments
GCC 8.1 vs. GCC 7.3 Compiler Benchmarks On Five AMD/Intel Linux Systems

With GCC 8.1 having been officially released last week, I have spent the past number of days running a variety of compiler benchmarks comparing this initial GCC8 stable release to the previous GCC 7.3 stable compiler release. Tests were done on five different Ubuntu 18.04 LTS Linux systems running very different AMD and Intel processors.

10 May 2018 - 15 Comments
Linux 4.17 Offers Some Promising Power-Savings Improvements

Of the many improvements to be found in the in-development Linux 4.17 kernel -- nicely summarized in our Linux 4.17 feature overview -- one of the features I've been anxious the most to begin benchmarking has been the reported power management improvements. Here are my initial power/performance tests of Linux 4.17 that for some systems is seeing a measurable drop in power usage, even in some cases under load while without sacrificing the performance.

15 April 2018 - 30 Comments
The Many Great Features & Changes Coming For The Linux 4.17 Kernel

Linus Torvalds is expected by the end of the day to release Linux 4.17-rc1, thereby marking the end of the two-week merge window that saw a lot of changes and new features land for Linux 4.17. Here is our original feature overview of the changes to be found in this next major release of the Linux kernel, which should premiere as stable by the middle of June.

15 April 2018 - 1 Comment
Linux 4.4 To 4.16 Kernel Benchmarks With AMD Ryzen Threadripper

This past weekend I posted some Linux 3.17 to Linux 4.16 kernel benchmarks using two older Intel hardware platforms and one of the most frequent requests to come in following that article were some AMD benchmarks looking at the Intel Linux performance going a ways back. Here are some test results from Linux 4.4 to 4.16 using an AMD Ryzen Threadripper 1950X system.

27 March 2018 - 7 Comments
Linux 3.17 To Linux 4.16 Kernel Benchmarks On Intel Gulftown & Haswell Hardware

Our latest benchmarking of the near-final Linux 4.16 kernel is checking on the performance of two Intel systems going back to the days of Linux 3.17, the oldest kernel that would successfully boot with the Ubuntu 18.04 user-space. Every major kernel release was tested as we see how the Linux kernel performance has evolved on these Haswell and Gulftown systems since October 2014.

25 March 2018 - 20 Comments
LLVM Clang 6.0 vs. 5.0 Compiler Performance On Intel/AMD Linux

Since last week's big release of LLVM 6.0 along with Clang 6.0, I have been carrying out some fresh compiler benchmarks of the previous Clang 5.0 to this new stable release that switches to C++14 by default, among many other changes to LLVM itself and this C/C++ compiler front-end.

14 March 2018 - 2 Comments
An Early Look At The Linux 4.16 Kernel Performance With AMD EPYC

A few days back I provided some fresh Linux 4.16 kernel benchmarks compared to recent stable kernel releases while also toggling the KPTI and Retpoline security features on Linux 4.16 Git for seeing the impact of the Spectre and Meltdown mitigation techniques on this latest kernel while using Intel Xeon hardware. For this latest round of tests is a similar comparison while using an AMD EPYC system.

10 March 2018 - 2 Comments
Bringing Open-Source, Automated Benchmarks To Windows 10 / Windows Server 2016

Moving forward the Phoronix Test Suite will be offering Microsoft Windows support that's at near feature parity to the automated, reproducible, open-source benchmarking support we have offered the past decade for Linux as well as BSD, macOS, and Solaris platforms. This is brand new, rewritten Windows support with a focus on Windows 10 x64 and Windows Server 2016.

8 March 2018 - 12 Comments
Benchmarking Amazon EC2 Instances vs. Various Intel/AMD CPUs

Given the recent performance changes following the Spectre/Meltdown CPU vulnerability mitigation and having just wrapped up some fresh CPU bare metal benchmarks as part of that testing as well as the recent AMD Raven Ridge launch, I've carried out a fresh round this week of benchmarks on various Amazon EC2 on-demand instance types compared to a number of bare metal Intel and AMD processors in looking at how the compute performance compares.

20 February 2018 - 12 Comments
A Look At The Plethora Of Linux 4.16 Kernel Features & Changes

After the lengthy Linux 4.15 kernel cycle, the past two weeks have marked the Linux 4.16 merge window. Yet again it's been another heavy feature period for the kernel. There is still a lot of mitigation work going on for most CPU architectures surrounding Spectre and also Meltdown, the open-source graphics drivers have continued getting better, various CPU improvements are present, the VirtualBox Guest driver was mainlined, and dozens of other notable changes for Linux 4.16. Take a look.

11 February 2018 - 5 Comments
AMD AOCC 1.1 Shows Compiler Improvements vs. GCC vs. Clang

A few days ago we found out that at the end of 2017 AMD quietly released their AOCC 1.1 C/C++ compiler. AOCC is AMD's compiler succeeding AMD Open64 that existed years ago as their optimized Fortran/C/C++ compiler for past CPU microarchitectures while the "AMD Optimizing C/C++ Compiler" is designed for current-generation Zen processors. Here are benchmarks of the new AMD AOCC 1.1 release compared to GCC 7, GCC 8, Clang 5.0, Clang 6.0, and Clang 7.0 SVN.

30 January 2018 - 13 Comments
Linux 4.0 To Linux 4.15 Kernel Benchmarks

Our latest in benchmarking the Linux 4.15 kernel is seeing how the performance has changed since Linux 4.0 and all subsequent releases on the same system. Here are those tests driven by curiosity, especially in light of the performance changes as a result of KPTI page table isolation and Retpoline additions.

24 January 2018 - 11 Comments
Benchmarking Retpoline-Enabled GCC 8 With -mindirect-branch=thunk

We have looked several times already at the performance impact of Retpoline support in the Linux kernel, but what about building user-space packages with -mindirect-branch=thunk? Here is the performance cost to building some performance tests in user-space with -mindirect-branch=thunk and -mindirect-branch=thunk-inline.

16 January 2018 - 5 Comments

606 software articles published on Phoronix.