From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx147.postini.com [74.125.245.147]) by kanga.kvack.org (Postfix) with SMTP id 918156B005A for ; Tue, 16 Oct 2012 08:56:05 -0400 (EDT) Received: by mail-bk0-f41.google.com with SMTP id jm1so2920358bkc.14 for ; Tue, 16 Oct 2012 05:56:03 -0700 (PDT) Subject: Re: [Q] Default SLAB allocator From: Eric Dumazet 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 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Ezequiel Garcia Cc: David Rientjes , Andi Kleen , Linux Kernel Mailing List , linux-mm@kvack.org, Tim Bird , celinux-dev@lists.celinuxforum.org 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, 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