Intel's Rewrite Of Linux MM CID Code Showing Some Nice Gains For AMD
([Software] 95 Minutes Ago
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- Reference: 0001589862
- News link: https://www.phoronix.com/review/rseq-cid-benchmarks
- Source link:
Posted last month were new Linux kernel scheduler-related patches rewriting the MM CID management code. The main takeaway for end-users from this set of 19 Linux kernel patches from an Intel engineer was [1]seeing 14~18% improvement in a PostgreSQL database benchmark but that more benchmarks were needed. Curiosity got the best of me and I recently tested these patches on an AMD EPYC server to seeing some very enticing results for this in-development code.
[2]
Those interested in all the low-level technical details of this MM CID management rewrite can see [3]this patch series from mid-October by Intel Fellow Thomas Gleixner. With the call-out for additional benchmarks from that patch series, I ran some benchmarks on an AMD EPYC test server for seeing the performance impact in some common server workloads.
For my testing I was running against Gleixner's [4]tglx/devel.git rseq/cid Git branch that contains his rseq/perf patches plus the MM CID code rewrite patches. He did post a new revision of the patches this week to that branch but my testing was done in October against his original patch series.
I compared the "rseq/cid" Git branch with these patches against a mainline Linux 6.19-rc1 Git kernel for which that branch was originally based. The same kernel configuration and compiler were used for both kernel builds.
Using a dual AMD EPYC 9965 server (combined 384 cores / 768 threads) and running Ubuntu 25.10 with these custom kernel builds tested, I ran dozens of different benchmarks to see the impact of the rseq/cid kernel patches compared to the upstream Linux 6.18 state. Benchmarks on additional hardware and of this week's very newest rseq/cid patches may come if there is sufficient Phoronix reader interest to justify the testing time needed.
[1] https://www.phoronix.com/news/Linux-MM-CID-Faster-DBs
[2] https://www.phoronix.com/image-viewer.php?id=rseq-cid-benchmarks&image=intel_amd_rseq_cid_lrg
[3] https://lore.kernel.org/lkml/20251015164952.694882104@linutronix.de/
[4] https://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git/log/?h=rseq/cid
[2]
Those interested in all the low-level technical details of this MM CID management rewrite can see [3]this patch series from mid-October by Intel Fellow Thomas Gleixner. With the call-out for additional benchmarks from that patch series, I ran some benchmarks on an AMD EPYC test server for seeing the performance impact in some common server workloads.
For my testing I was running against Gleixner's [4]tglx/devel.git rseq/cid Git branch that contains his rseq/perf patches plus the MM CID code rewrite patches. He did post a new revision of the patches this week to that branch but my testing was done in October against his original patch series.
I compared the "rseq/cid" Git branch with these patches against a mainline Linux 6.19-rc1 Git kernel for which that branch was originally based. The same kernel configuration and compiler were used for both kernel builds.
Using a dual AMD EPYC 9965 server (combined 384 cores / 768 threads) and running Ubuntu 25.10 with these custom kernel builds tested, I ran dozens of different benchmarks to see the impact of the rseq/cid kernel patches compared to the upstream Linux 6.18 state. Benchmarks on additional hardware and of this week's very newest rseq/cid patches may come if there is sufficient Phoronix reader interest to justify the testing time needed.
[1] https://www.phoronix.com/news/Linux-MM-CID-Faster-DBs
[2] https://www.phoronix.com/image-viewer.php?id=rseq-cid-benchmarks&image=intel_amd_rseq_cid_lrg
[3] https://lore.kernel.org/lkml/20251015164952.694882104@linutronix.de/
[4] https://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git/log/?h=rseq/cid