Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Fri, 8 Feb 2019 16:38:09 -0500
From:   "Michael S. Tsirkin" <mst@redhat.com>
To:     Nitesh Narayan Lal <nitesh@redhat.com>
Cc:     Alexander Duyck <alexander.duyck@gmail.com>,
        kvm list <kvm@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Paolo Bonzini <pbonzini@redhat.com>, lcapitulino@redhat.com,
        pagupta@redhat.com, wei.w.wang@intel.com,
        Yang Zhang <yang.zhang.wz@gmail.com>,
        Rik van Riel <riel@surriel.com>, david@redhat.com,
        dodgen@google.com, Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
        dhildenb@redhat.com, Andrea Arcangeli <aarcange@redhat.com>
Subject: Re: [RFC][Patch v8 6/7] KVM: Enables the kernel to isolate and
 report free pages
Message-ID: <20190208163601-mutt-send-email-mst@kernel.org>
References: <20190204201854.2328-1-nitesh@redhat.com>
 <20190204201854.2328-7-nitesh@redhat.com>
 <20190205153607-mutt-send-email-mst@kernel.org>
 <ab671cf4-f379-7be7-50d3-ffb41c3b91ba@redhat.com>
 <20190205165514-mutt-send-email-mst@kernel.org>
 <CAKgT0UdcrbUw-wfeXQPjnnbTWrvNB0zpwq-bCv4EEWcOSizL_w@mail.gmail.com>
 <ab03c35e-b2bb-cb96-4701-436a4e2770d1@redhat.com>
 <CAKgT0UcEFi7Rq9+EnLNNm61782QYRT6XZQDgbWFt2S8eMLf=qA@mail.gmail.com>
 <e304f4ed-5aea-4a2b-1b83-7d4f8bb37e6e@redhat.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <e304f4ed-5aea-4a2b-1b83-7d4f8bb37e6e@redhat.com>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Fri, Feb 08, 2019 at 03:41:55PM -0500, Nitesh Narayan Lal wrote:
> >> I am also planning to try Michael's suggestion of using MAX_ORDER - 1.
> >> However I am still thinking about a workload which I can use to test its
> >> effectiveness.
> > You might want to look at doing something like min(MAX_ORDER - 1,
> > HUGETLB_PAGE_ORDER). I know for x86 a 2MB page is the upper limit for
> > THP which is the most likely to be used page size with the guest.
> Sure, thanks for the suggestion.

Given current hinting in balloon is MAX_ORDER I'd say
share code. If you feel a need to adjust down the road,
adjust both of them with actual testing showing gains.

-- 
MST