Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754472Ab2JPM4H (ORCPT ); Tue, 16 Oct 2012 08:56:07 -0400 Received: from mail-bk0-f46.google.com ([209.85.214.46]:40286 "EHLO mail-bk0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753173Ab2JPM4F (ORCPT ); Tue, 16 Oct 2012 08:56:05 -0400 Subject: Re: [Q] Default SLAB allocator From: Eric Dumazet To: Ezequiel Garcia Cc: David Rientjes , Andi Kleen , Linux Kernel Mailing List , linux-mm@kvack.org, Tim Bird , celinux-dev@lists.celinuxforum.org In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Date: Tue, 16 Oct 2012 14:56:00 +0200 Message-ID: <1350392160.3954.986.camel@edumazet-glaptop> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 759 Lines: 21 On Tue, 2012-10-16 at 09:35 -0300, Ezequiel Garcia wrote: > Now, returning to the fragmentation. The problem with SLAB is that > its smaller cache available for kmalloced objects is 32 bytes; > while SLUB allows 8, 16, 24 ... > > Perhaps adding smaller caches to SLAB might make sense? > Is there any strong reason for NOT doing this? I would remove small kmalloc-XX caches, as sharing a cache line is sometime dangerous for performance, because of false sharing. They make sense only for very small hosts. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/