From: Dave Hansen <dave.hansen@intel.com>
To: Chengfeng Lin <lin2530632123@gmail.com>,
Pawan Gupta <pawan.kumar.gupta@linux.intel.com>,
Dave Hansen <dave.hansen@linux.intel.com>,
Daniel Borkmann <daniel@iogearbox.net>
Cc: x86@kernel.org, bpf@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [linus:master] [x86/bugs] a3af84b0fa: stress-ng.seccomp.ops_per_sec 95.7% regression
Date: Wed, 4 Nov 2026 07:19:07 -0800 [thread overview]
Message-ID: <84ecf492-5a71-4871-a555-abb76a1402db@intel.com> (raw)
In-Reply-To: <179361623876.3.16264907931792312619.redis-ibpb-report@gmail.com>
On 11/2/26 02:43, Chengfeng Lin wrote:
> I found another workload affected by a3af84b0fa00 while running MMTests:
> Redis ZPOPMIN throughput on v7.3 is about 13% lower than on v7.1.3.
> Unlike the repeated filter loading discussed here, the slowdown remains
> after the tasks that triggered the predictor flush (IBPB) have exited.
> Can this cost be reduced while preserving the security protection?
To answer the question: I don't see anything obvious. These performance
issues where the overhead is smeared across a bunch of places are among
the most difficult to figure out.
All I can suggest is to have the LLM that you've been using so far do
some more digging and see if it can come up with anything else.
next prev parent reply other threads:[~2026-11-04 15:19 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-08-19 6:20 kernel test robot
2026-08-19 15:26 ` Dave Hansen
2026-08-19 18:59 ` Pawan Gupta
2026-11-02 10:43 ` Chengfeng Lin
2026-11-02 19:31 ` Pawan Gupta
2026-11-03 15:23 ` Dave Hansen
2026-11-04 15:07 ` Chengfeng Lin
2026-11-04 15:19 ` Dave Hansen [this message]
2026-11-04 15:36 ` Chengfeng Lin
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