Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751108AbWHFNzF (ORCPT ); Sun, 6 Aug 2006 09:55:05 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751154AbWHFNzF (ORCPT ); Sun, 6 Aug 2006 09:55:05 -0400 Received: from smtprelay05.ispgateway.de ([80.67.18.43]:16871 "EHLO smtprelay05.ispgateway.de") by vger.kernel.org with ESMTP id S1751108AbWHFNzD (ORCPT ); Sun, 6 Aug 2006 09:55:03 -0400 From: Matthias Dahl To: linux-kernel@vger.kernel.org Subject: Re: sluggish system responsiveness under higher IO load Date: Sun, 6 Aug 2006 15:54:42 +0200 User-Agent: KMail/1.9.4 References: <200608061200.37701.mlkernel@mortal-soul.de> <20060806031512.57585f5d.akpm@osdl.org> In-Reply-To: <20060806031512.57585f5d.akpm@osdl.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200608061554.42992.mlkernel@mortal-soul.de> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6432 Lines: 97 > I'd suggest that you generate a kernel profile while the sluggishness is > happening. Done... profile 1: (emerge of three huge packages which caused quite some IO) ffffffff80232650 __wake_up 23 0.2396 ffffffff803427a0 vgacon_cursor 23 0.0395 ffffffff8020ba40 free_hot_cold_page 24 0.0652 ffffffff8020be90 find_vma 25 0.2232 ffffffff8020c9b0 __wake_up_bit 25 0.5208 ffffffff80301800 journal_add_journal_head 25 0.0601 ffffffff803424e0 vgacon_scroll 26 0.0478 ffffffff802eb970 __ext3_get_inode_loc 27 0.0312 ffffffff802fd8e0 journal_dirty_metadata 27 0.0456 ffffffff80207500 kmem_cache_free 28 0.2917 ffffffff80211d90 do_select 30 0.0216 ffffffff8020d420 bit_waitqueue 32 0.1429 ffffffff8020bbb0 fget_light 34 0.1635 ffffffff8026b97f thread_return 35 0.1211 ffffffff80268d50 system_call 36 0.2748 ffffffff8020a580 kmem_cache_alloc 39 0.6094 ffffffff8020cae0 vm_normal_page 42 0.2188 ffffffff8020bf00 __make_request 43 0.0384 ffffffff8020b600 __find_get_block 47 0.0979 ffffffff802eb5c0 ext3_mark_iloc_dirty 48 0.0508 ffffffff8020a0f0 get_page_from_freelist 50 0.0428 ffffffff802fba50 do_get_write_access 55 0.0382 ffffffff80209050 __link_path_walk 56 0.0132 ffffffff803a63a0 scsi_request_fn 57 0.0604 ffffffff8026b0c0 memcpy 59 0.3352 ffffffff8020ccf0 __delay 69 2.1562 ffffffff80208350 __handle_mm_fault 78 0.0269 ffffffff802075e0 unmap_vmas 93 0.0501 ffffffff80208ea0 __d_lookup 95 0.2199 ffffffff8026ad30 clear_page 100 1.7544 ffffffff80341880 vgacon_set_cursor_size 103 0.4023 ffffffff8020a920 do_page_fault 105 0.0443 ffffffff80207560 find_get_page 106 0.9464 ffffffff80207d20 copy_page_range 111 0.0701 ffffffff8026ad70 copy_page 157 0.7009 ffffffff80212cd0 __do_softirq 189 1.0739 ffffffff803a0430 scsi_dispatch_cmd 459 0.7172 ffffffff8026afda copy_user_generic_c 854 22.4737 ffffffff80270e00 default_idle 49571 516.3646 0000000000000000 total 54590 0.0232 profile 2: (emerge of recent kernel sources- huge, causes quite some IO too) ffffffff8020ff40 generic_permission 57 0.2227 ffffffff8020ccf0 __delay 58 1.8125 ffffffff802149a0 rb_insert_color 58 0.2417 ffffffff802af8b0 free_page_and_swap_cache 63 1.3125 ffffffff8020ccb0 put_page 66 1.0312 ffffffff803a63a0 scsi_request_fn 67 0.0710 ffffffff80234c60 unix_poll 69 0.3920 ffffffff8020b600 __find_get_block 74 0.1542 ffffffff80268d50 system_call 81 0.6183 ffffffff8020e220 memscan 88 1.8333 ffffffff80224820 __up_read 92 0.5227 ffffffff802fba50 do_get_write_access 95 0.0660 ffffffff80207500 kmem_cache_free 99 1.0312 ffffffff80223d40 find_next_zero_bit 100 0.6944 ffffffff8020d6a0 strncpy_from_user 103 1.2875 ffffffff80211d90 do_select 104 0.0747 ffffffff8020c9b0 __wake_up_bit 117 2.4375 ffffffff8026b97f thread_return 120 0.4152 ffffffff8020a580 kmem_cache_alloc 143 2.2344 ffffffff8026b0c0 memcpy 154 0.8750 ffffffff8020a0f0 get_page_from_freelist 155 0.1327 ffffffff8020b260 page_remove_rmap 172 2.6875 ffffffff80221320 copy_process 175 0.0315 ffffffff80207560 find_get_page 190 1.6964 ffffffff8020be90 find_vma 198 1.7679 ffffffff80211900 do_wp_page 249 0.2132 ffffffff80209050 __link_path_walk 315 0.0740 ffffffff8026afda copy_user_generic_c 325 8.5526 ffffffff80212cd0 __do_softirq 452 2.5682 ffffffff80208350 __handle_mm_fault 479 0.1654 ffffffff80208ea0 __d_lookup 510 1.1806 ffffffff8026ad30 clear_page 519 9.1053 ffffffff803a0430 scsi_dispatch_cmd 576 0.9000 ffffffff8020a920 do_page_fault 712 0.3007 ffffffff8020cae0 vm_normal_page 814 4.2396 ffffffff8026ad70 copy_page 1929 8.6116 ffffffff802075e0 unmap_vmas 2362 1.2726 ffffffff80207d20 copy_page_range 2683 1.6938 ffffffff80270e00 default_idle 45081 469.5938 0000000000000000 total 64216 0.0273 I hope this helps. - 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/