From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Sat, 16 Feb 2008 14:09:54 -0800 (PST) From: Christoph Lameter Subject: Re: [patch 7/8] slub: Adjust order boundaries and minimum objects per slab. In-Reply-To: <1203193259.6324.12.camel@cinder.waste.org> Message-ID: References: <20080215230811.635628223@sgi.com> <20080215230854.643455255@sgi.com> <47B6A928.7000309@cs.helsinki.fi> <1203193259.6324.12.camel@cinder.waste.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: Matt Mackall Cc: Pekka Enberg , Mel Gorman , linux-mm@kvack.org List-ID: On Sat, 16 Feb 2008, Matt Mackall wrote: > Why are 4k objects even going through SLUB? Because the page allocator is slower by factor 8. > What happens if we have 8k free and try to allocate one 4k object > through SLUB? We allocate one page and return it. > Using an order greater than 0 is generally frowned upon. Kernels can and > do get into situations where they can't find two contiguous pages, which > is why we've gone to so much trouble on x86 to fit into a single page of > stack. All allocations can fall back to order 0 allocs with the patchset we are discussing. -- 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