Re: [PATCH v2] KVM: PPC: e500mc: Enhance tlb invalidation condition on vcpu schedule
On Tue, 2014-06-17 at 14:04 -0500, Caraman Mihai Claudiu-B02008 wrote: > > -Original Message- > > From: Wood Scott-B07421 > > Sent: Tuesday, June 17, 2014 6:36 PM > > To: Caraman Mihai Claudiu-B02008 > > Cc: kvm-...@vger.kernel.org; k...@vger.kernel.org; linuxppc- > > d...@lists.ozlabs.org > > Subject: Re: [PATCH v2] KVM: PPC: e500mc: Enhance tlb invalidation > > condition on vcpu schedule > > > > On Tue, 2014-06-17 at 12:02 +0300, Mihai Caraman wrote: > > > On vcpu schedule, the condition checked for tlb pollution is too loose. > > > The tlb entries of a vcpu become polluted (vs stale) only when a > > different > > > vcpu within the same logical partition runs in-between. Optimize the > > tlb > > > invalidation condition taking into account the logical partition id. > > > > > > With the new invalidation condition, a guest shows 4% performance > > improvement > > > on P5020DS while running a memory stress application with the cpu > > oversubscribed, > > > the other guest running a cpu intensive workload. > > > > See > > https://lists.ozlabs.org/pipermail/linuxppc-dev/2014-June/118547.html > > Thanks. The original code needs just a simple adjustment to benefit from > this optimization, please review v3. Where is v3? Or is it forthcoming? -Scott ___ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
RE: [PATCH v2] KVM: PPC: e500mc: Enhance tlb invalidation condition on vcpu schedule
> -Original Message- > From: Wood Scott-B07421 > Sent: Tuesday, June 17, 2014 6:36 PM > To: Caraman Mihai Claudiu-B02008 > Cc: kvm-...@vger.kernel.org; k...@vger.kernel.org; linuxppc- > d...@lists.ozlabs.org > Subject: Re: [PATCH v2] KVM: PPC: e500mc: Enhance tlb invalidation > condition on vcpu schedule > > On Tue, 2014-06-17 at 12:02 +0300, Mihai Caraman wrote: > > On vcpu schedule, the condition checked for tlb pollution is too loose. > > The tlb entries of a vcpu become polluted (vs stale) only when a > different > > vcpu within the same logical partition runs in-between. Optimize the > tlb > > invalidation condition taking into account the logical partition id. > > > > With the new invalidation condition, a guest shows 4% performance > improvement > > on P5020DS while running a memory stress application with the cpu > oversubscribed, > > the other guest running a cpu intensive workload. > > See > https://lists.ozlabs.org/pipermail/linuxppc-dev/2014-June/118547.html Thanks. The original code needs just a simple adjustment to benefit from this optimization, please review v3. - Mike ___ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
Re: [PATCH v2] KVM: PPC: e500mc: Enhance tlb invalidation condition on vcpu schedule
On Tue, 2014-06-17 at 12:02 +0300, Mihai Caraman wrote: > On vcpu schedule, the condition checked for tlb pollution is too loose. > The tlb entries of a vcpu become polluted (vs stale) only when a different > vcpu within the same logical partition runs in-between. Optimize the tlb > invalidation condition taking into account the logical partition id. > > With the new invalidation condition, a guest shows 4% performance improvement > on P5020DS while running a memory stress application with the cpu > oversubscribed, > the other guest running a cpu intensive workload. See https://lists.ozlabs.org/pipermail/linuxppc-dev/2014-June/118547.html -Scott ___ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
