From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ozlabs.org (ozlabs.org [IPv6:2401:3900:2:1::2]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 40GTBZ0xmvzDqGZ for ; Thu, 5 Apr 2018 00:39:50 +1000 (AEST) In-Reply-To: <20180322084350.21249-1-aneesh.kumar@linux.vnet.ibm.com> To: "Aneesh Kumar K.V" , benh@kernel.crashing.org, paulus@samba.org From: Michael Ellerman Cc: linuxppc-dev@lists.ozlabs.org, "Aneesh Kumar K.V" Subject: Re: [V2] powerpc/mm/radix: Update pte fragment count from 16 to 256 on radix Message-Id: <40GTBZ061Xz9s1r@ozlabs.org> Date: Thu, 5 Apr 2018 00:39:49 +1000 (AEST) List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Thu, 2018-03-22 at 08:43:50 UTC, "Aneesh Kumar K.V" wrote: > Right now we use only 4K out of the 64k page allocated for the level 4 page > table. W.r.t the performance impact due to lock contention, with ebizzy > > 256 threads: > without patch (10 runs of ./ebizzy -m -n 1000 -s 131072 -S 100) > median = 15678.5 > stdev = 42.1209 > > with patch: > median = 15354 > stdev = 194.743 > > This is with THP disabled. With THP enabled the impact of the patch will be less. > > Signed-off-by: Aneesh Kumar K.V Applied to powerpc next, thanks. https://git.kernel.org/powerpc/c/fb4e5dbd44564077fa0267a59b4596 cheers