Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030501AbVKPU4i (ORCPT ); Wed, 16 Nov 2005 15:56:38 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030491AbVKPU4i (ORCPT ); Wed, 16 Nov 2005 15:56:38 -0500 Received: from web34112.mail.mud.yahoo.com ([66.163.178.110]:30384 "HELO web34112.mail.mud.yahoo.com") by vger.kernel.org with SMTP id S1030501AbVKPU4h (ORCPT ); Wed, 16 Nov 2005 15:56:37 -0500 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com; h=Message-ID:Received:Date:From:Subject:To:Cc:In-Reply-To:MIME-Version:Content-Type:Content-Transfer-Encoding; b=Xi+vcHrfCQcsZY/O0YlAkyeHomae8KLrBR8LmZ2GNGjSAR4sIpR3eR6ikiPHLYwmVwt7rkBquwOtfnaGIn7oWiAgbP+vSTM3OfUtSWC7A0+Ib6gRifxKe6BiX7YhBojAcxhD7O0Kbzg5L92NI7tLeM6zCwqL2rl3pUDQxzSDFxo= ; Message-ID: <20051116205637.88606.qmail@web34112.mail.mud.yahoo.com> Date: Wed, 16 Nov 2005 12:56:36 -0800 (PST) From: Kenny Simpson Subject: Re: mmap over nfs leads to excessive system load To: Trond Myklebust , Andrew Morton Cc: theonetruekenny@yahoo.com, linux-kernel@vger.kernel.org In-Reply-To: <1132171500.8811.37.camel@lade.trondhjem.org> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1293 Lines: 39 I tried the same test, but instead of ftruncate64, I simply did a pwrite64 to get the file extended... and got 40M+ with mostly outbound traffic, and much less CPU usage..... Unfortunately, once my test file hit 4295065601, Bad Things (TM) started to happen. The system time went to 100% of a CPU, and the nfs traffic on that mount stopped. I got an oprofile of the spinning system: samples % symbol name 301039 27.9748 zap_pte_range 156234 14.5184 unmap_vmas 111760 10.3856 __bitmap_weight 103624 9.6295 _spin_lock 97063 9.0198 unmap_page_range 67011 6.2272 unmap_mapping_range 59382 5.5182 sub_preempt_count 51258 4.7633 zap_page_range 25235 2.3450 page_address 16768 1.5582 unmap_mapping_range_vma 13257 1.2319 debug_smp_processor_id 11594 1.0774 add_preempt_count I also seem unable to kill the test process. Any ideas? (2**32 file size issue somewhere?) -Kenny __________________________________ Yahoo! Mail - PC Magazine Editors' Choice 2005 http://mail.yahoo.com - 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/