Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752257Ab0HTKJF (ORCPT ); Fri, 20 Aug 2010 06:09:05 -0400 Received: from mga11.intel.com ([192.55.52.93]:28246 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752210Ab0HTKJB (ORCPT ); Fri, 20 Aug 2010 06:09:01 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.56,238,1280732400"; d="scan'208";a="830104140" Date: Fri, 20 Aug 2010 18:08:56 +0800 From: Wu Fengguang To: Michael Rubin Cc: "linux-kernel@vger.kernel.org" , "linux-fsdevel@vger.kernel.org" , "linux-mm@kvack.org" , "jack@suse.cz" , "riel@redhat.com" , "akpm@linux-foundation.org" , "david@fromorbit.com" , "npiggin@kernel.dk" , "hch@lst.de" , "axboe@kernel.dk" Subject: Re: [PATCH 3/4] writeback: nr_dirtied and nr_entered_writeback in /proc/vmstat Message-ID: <20100820100855.GC8440@localhost> References: <1282296689-25618-1-git-send-email-mrubin@google.com> <1282296689-25618-4-git-send-email-mrubin@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1282296689-25618-4-git-send-email-mrubin@google.com> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5718 Lines: 157 On Fri, Aug 20, 2010 at 05:31:28PM +0800, Michael Rubin wrote: > To help developers and applications gain visibility into writeback > behaviour adding two entries to /proc/vmstat. > > # grep nr_dirtied /proc/vmstat > nr_dirtied 3747 > # grep nr_entered_writeback /proc/vmstat > nr_entered_writeback 3618 How about the names nr_dirty_accumulated and nr_writeback_accumulated? It seems more consistent, for both the interface and code (see below). I'm not really sure though. > In order to track the "cleaned" and "dirtied" counts we added two > vm_stat_items. Per memory node stats have been added also. So we can > see per node granularity: > > # cat /sys/devices/system/node/node20/writebackstat > Node 20 pages_writeback: 0 times > Node 20 pages_dirtied: 0 times I'd prefer the name "vmstat" over "writebackstat", and propose to migrate items from /proc/zoneinfo over time. zoneinfo is a terrible interface for scripting. Also, are there meaningful usage of per-node writeback stats? The numbers are naturally per-bdi ones instead. But if we plan to expose them for each bdi, this patch will need to be implemented vastly differently. > Signed-off-by: Michael Rubin > --- > drivers/base/node.c | 14 ++++++++++++++ > include/linux/mmzone.h | 2 ++ > mm/page-writeback.c | 2 ++ > mm/vmstat.c | 3 +++ > 4 files changed, 21 insertions(+), 0 deletions(-) > > diff --git a/drivers/base/node.c b/drivers/base/node.c > index 2872e86..2d05421 100644 > --- a/drivers/base/node.c > +++ b/drivers/base/node.c > @@ -160,6 +160,18 @@ static ssize_t node_read_numastat(struct sys_device * dev, > } > static SYSDEV_ATTR(numastat, S_IRUGO, node_read_numastat, NULL); > > +static ssize_t node_read_writebackstat(struct sys_device *dev, > + struct sysdev_attribute *attr, char *buf) > +{ > + int nid = dev->id; > + return sprintf(buf, > + "Node %d pages_writeback: %lu times\n" > + "Node %d pages_dirtied: %lu times\n", > + nid, node_page_state(nid, NR_PAGES_ENTERED_WRITEBACK), > + nid, node_page_state(nid, NR_FILE_PAGES_DIRTIED)); nid, node_page_state(nid, NR_WRITEBACK_ACCUMULATED), nid, node_page_state(nid, NR_FILE_DIRTY_ACCUMULATED)); > +} > +static SYSDEV_ATTR(writebackstat, S_IRUGO, node_read_writebackstat, NULL); > + s/writebackstat/vmstat/ > static ssize_t node_read_distance(struct sys_device * dev, > struct sysdev_attribute *attr, char * buf) > { > @@ -243,6 +255,7 @@ int register_node(struct node *node, int num, struct node *parent) > sysdev_create_file(&node->sysdev, &attr_meminfo); > sysdev_create_file(&node->sysdev, &attr_numastat); > sysdev_create_file(&node->sysdev, &attr_distance); > + sysdev_create_file(&node->sysdev, &attr_writebackstat); ditto s/writebackstat/vmstat/ > scan_unevictable_register_node(node); > > @@ -267,6 +280,7 @@ void unregister_node(struct node *node) > sysdev_remove_file(&node->sysdev, &attr_meminfo); > sysdev_remove_file(&node->sysdev, &attr_numastat); > sysdev_remove_file(&node->sysdev, &attr_distance); > + sysdev_remove_file(&node->sysdev, &attr_writebackstat); ditto s/writebackstat/vmstat/ > scan_unevictable_unregister_node(node); > hugetlb_unregister_node(node); /* no-op, if memoryless node */ > diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h > index 6e6e626..fe4e6dd 100644 > --- a/include/linux/mmzone.h > +++ b/include/linux/mmzone.h > @@ -104,6 +104,8 @@ enum zone_stat_item { > NR_ISOLATED_ANON, /* Temporary isolated pages from anon lru */ > NR_ISOLATED_FILE, /* Temporary isolated pages from file lru */ > NR_SHMEM, /* shmem pages (included tmpfs/GEM pages) */ > + NR_FILE_PAGES_DIRTIED, /* number of times pages get dirtied */ > + NR_PAGES_ENTERED_WRITEBACK, /* number of times pages enter writeback */ NR_FILE_DIRTY_ACCUMULATED, /* number of times pages get dirtied */ NR_WRITEBACK_ACCUMULATED, /* number of times pages enter writeback */ > #ifdef CONFIG_NUMA > NUMA_HIT, /* allocated in intended node */ > NUMA_MISS, /* allocated in non intended node */ > diff --git a/mm/page-writeback.c b/mm/page-writeback.c > index ae5f5d5..1b1763c 100644 > --- a/mm/page-writeback.c > +++ b/mm/page-writeback.c > @@ -1126,6 +1126,7 @@ void account_page_dirtied(struct page *page, struct address_space *mapping) > { > if (mapping_cap_account_dirty(mapping)) { > __inc_zone_page_state(page, NR_FILE_DIRTY); > + __inc_zone_page_state(page, NR_FILE_PAGES_DIRTIED); __inc_zone_page_state(page, NR_FILE_DIRTY_ACCUMULATED); > __inc_bdi_stat(mapping->backing_dev_info, BDI_RECLAIMABLE); > task_dirty_inc(current); > task_io_account_write(PAGE_CACHE_SIZE); > @@ -1141,6 +1142,7 @@ EXPORT_SYMBOL(account_page_dirtied); > void account_page_writeback(struct page *page) > { > inc_zone_page_state(page, NR_WRITEBACK); > + inc_zone_page_state(page, NR_PAGES_ENTERED_WRITEBACK); inc_zone_page_state(page, NR_WRITEBACK_ACCUMULATED); > } > EXPORT_SYMBOL(account_page_writeback); > > diff --git a/mm/vmstat.c b/mm/vmstat.c > index f389168..073a496 100644 > --- a/mm/vmstat.c > +++ b/mm/vmstat.c > @@ -732,6 +732,9 @@ static const char * const vmstat_text[] = { > "nr_isolated_anon", > "nr_isolated_file", > "nr_shmem", > + "nr_dirtied", > + "nr_entered_writeback", "nr_dirty_accumulated", "nr_writeback_accumulated", > #ifdef CONFIG_NUMA > "numa_hit", > "numa_miss", > -- > 1.7.1 -- 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/