From: Sean Christopherson <seanjc@google.com>
To: Peng Hao <flyingpenghao@gmail.com>
Cc: pbonzini@redhat.com, kvm@vger.kernel.org
Subject: Re: [PATCH] KVM: Add Kconfig to compile out the halt-polling histograms
Date: Wed, 11 Nov 2026 08:13:08 -0800 [thread overview]
Message-ID: <avSUFJEEubkNldb8@seanjc-mac.roam.internal> (raw)
In-Reply-To: <20261111015446.20577-1-flyingpeng@tencent.com>
On Wed, Nov 11, 2026, Peng Hao wrote:
> The halt_poll_success_hist, halt_poll_fail_hist and halt_wait_hist
> histograms in struct kvm_vcpu_stat_generic take 768 bytes in every vCPU.
> Add CONFIG_KVM_HALT_POLL_HISTOGRAMS (default y) so that they can be
> compiled out.
I'm not a huge fan of adding Kconfigs for stats. I worry that we'll end up with
a mess of Kconfigs that only a few companies in the world can actually use.
I do 100% agree that the histograms are dead weight for many setups, I just don't
like the idea of using user-visible Kconfigs to deal with stats. And whatever we
do, I'd like to have a plan for stats in general, i.e. not just fix one-off things,
but come up with a long-term plan for how we want to handle stats in upstream (this
isn't the first time memory usage related to stats has come up).
prev parent reply other threads:[~2026-11-11 16:13 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-11-11 1:54 [PATCH] KVM: Add Kconfig to compile out the halt-polling histograms Peng Hao
2026-11-11 16:13 ` Sean Christopherson [this message]
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