From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mel Gorman Subject: Re: [PATCHv6 00/22] Transparent huge page cache: phase 1, everything but mmap() Date: Mon, 30 Sep 2013 11:10:29 +0100 Message-ID: <20130930101029.GC2425@suse.de> References: <1379937950-8411-1-git-send-email-kirill.shutemov@linux.intel.com> <20130924163740.4bc7db61e3e520798220dc4c@linux-foundation.org> <20130930100249.GB2425@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Cc: "Kirill A. Shutemov" , Andrea Arcangeli , Al Viro , Hugh Dickins , Wu Fengguang , Jan Kara , linux-mm@kvack.org, Andi Kleen , Matthew Wilcox , "Kirill A. Shutemov" , Hillf Danton , Dave Hansen , Ning Qu , Alexander Shishkin , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org To: Andrew Morton Return-path: Content-Disposition: inline In-Reply-To: <20130930100249.GB2425@suse.de> Sender: owner-linux-mm@kvack.org List-Id: linux-fsdevel.vger.kernel.org On Mon, Sep 30, 2013 at 11:02:49AM +0100, Mel Gorman wrote: > On Tue, Sep 24, 2013 at 04:37:40PM -0700, Andrew Morton wrote: > > On Mon, 23 Sep 2013 15:05:28 +0300 "Kirill A. Shutemov" wrote: > > > > > It brings thp support for ramfs, but without mmap() -- it will be posted > > > separately. > > > > We were never going to do this :( > > > > Has anyone reviewed these patches much yet? > > > > I am afraid I never looked too closely once I learned that the primary > motivation for this was relieving iTLB pressure in a very specific > case. AFAIK, this is not a problem in the vast majority of modern CPUs > and I found it very hard to be motivated to review the series as a result. > I suspected that in many cases that the cost of IO would continue to dominate > performance instead of TLB pressure. I also found it unlikely that there > was a workload that was tmpfs based that used enough memory to be hurt > by TLB pressure. My feedback was that a much more compelling case for the > series was needed but this discussion all happened on IRC unfortunately. > Oh, one last thing I forgot. While tmpfs-based workloads were not likely to benefit I would expect that sysV shared memory workloads would potentially benefit from this. hugetlbfs is still required for shared memory areas but it is not a problem that is addressed by this series. -- Mel Gorman SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org