From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mel Gorman Message-Id: <20051005144623.11796.99869.sendpatchset@skynet.csn.ul.ie> In-Reply-To: <20051005144546.11796.1154.sendpatchset@skynet.csn.ul.ie> References: <20051005144546.11796.1154.sendpatchset@skynet.csn.ul.ie> Subject: [PATCH 7/7] Fragmentation Avoidance V16: 007_stats Date: Wed, 5 Oct 2005 15:46:23 +0100 (IST) Sender: owner-linux-mm@kvack.org Return-Path: To: linux-mm@kvack.org Cc: akpm@osdl.org, Mel Gorman , kravetz@us.ibm.com, linux-kernel@vger.kernel.org, jschopp@austin.ibm.com, lhms-devel@lists.sourceforge.net List-ID: It is not necessary to apply this patch to get all the anti-fragmentation code. This patch adds a new config option called CONFIG_ALLOCSTATS. If set, a number of new bean counters are added that are related to the anti-fragmentation code. The information is exported via /proc/buddyinfo. This is very useful when debugging why high-order pages are not available for allocation. Signed-off-by: Mel Gorman diff -rup -X /usr/src/patchset-0.5/bin//dontdiff linux-2.6.14-rc3-006_percpu/include/linux/mmzone.h linux-2.6.14-rc3-007_stats/include/linux/mmzone.h --- linux-2.6.14-rc3-006_percpu/include/linux/mmzone.h 2005-10-05 12:26:56.000000000 +0100 +++ linux-2.6.14-rc3-007_stats/include/linux/mmzone.h 2005-10-05 12:29:57.000000000 +0100 @@ -176,6 +176,19 @@ struct zone { unsigned long fallback_reserve; long fallback_balance; +#ifdef CONFIG_ALLOCSTATS + /* + * These are beancounters that track how the placement policy + * of the buddy allocator is performing + */ + unsigned long fallback_count[RCLM_TYPES]; + unsigned long alloc_count[RCLM_TYPES]; + unsigned long reserve_count[RCLM_TYPES]; + unsigned long kernnorclm_full_steal; + unsigned long kernnorclm_partial_steal; +#endif + + ZONE_PADDING(_pad1_) /* Fields commonly accessed by the page reclaim scanner */ @@ -265,6 +278,17 @@ struct zone { char *name; } ____cacheline_maxaligned_in_smp; +#ifdef CONFIG_ALLOCSTATS +#define inc_fallback_count(zone, type) zone->fallback_count[type]++ +#define inc_alloc_count(zone, type) zone->alloc_count[type]++ +#define inc_kernnorclm_partial_steal(zone) zone->kernnorclm_partial_steal++ +#define inc_kernnorclm_full_steal(zone) zone->kernnorclm_full_steal++ +#else +#define inc_fallback_count(zone, type) do {} while (0) +#define inc_alloc_count(zone, type) do {} while (0) +#define inc_kernnorclm_partial_steal(zone) do {} while (0) +#define inc_kernnorclm_full_steal(zone) do {} while (0) +#endif /* * The "priority" of VM scanning is how much of the queues we will scan in one diff -rup -X /usr/src/patchset-0.5/bin//dontdiff linux-2.6.14-rc3-006_percpu/lib/Kconfig.debug linux-2.6.14-rc3-007_stats/lib/Kconfig.debug --- linux-2.6.14-rc3-006_percpu/lib/Kconfig.debug 2005-10-04 22:58:34.000000000 +0100 +++ linux-2.6.14-rc3-007_stats/lib/Kconfig.debug 2005-10-05 12:29:57.000000000 +0100 @@ -77,6 +77,17 @@ config SCHEDSTATS application, you can say N to avoid the very slight overhead this adds. +config ALLOCSTATS + bool "Collection buddy allocator statistics" + depends on DEBUG_KERNEL && PROC_FS + help + If you say Y here, additional code will be inserted into the + page allocator routines to collect statistics on the allocator + behavior and provide them in /proc/buddyinfo. These stats are + useful for measuring fragmentation in the buddy allocator. If + you are not debugging or measuring the allocator, you can say N + to avoid the slight overhead this adds. + config DEBUG_SLAB bool "Debug memory allocations" depends on DEBUG_KERNEL diff -rup -X /usr/src/patchset-0.5/bin//dontdiff linux-2.6.14-rc3-006_percpu/mm/page_alloc.c linux-2.6.14-rc3-007_stats/mm/page_alloc.c --- linux-2.6.14-rc3-006_percpu/mm/page_alloc.c 2005-10-05 12:27:48.000000000 +0100 +++ linux-2.6.14-rc3-007_stats/mm/page_alloc.c 2005-10-05 12:29:57.000000000 +0100 @@ -191,6 +191,11 @@ EXPORT_SYMBOL(zone_table); static char *zone_names[MAX_NR_ZONES] = { "DMA", "Normal", "HighMem" }; int min_free_kbytes = 1024; +#ifdef CONFIG_ALLOCSTATS +static char *type_names[RCLM_TYPES] = { "KernNoRclm", "UserRclm", + "KernRclm", "Fallback"}; +#endif /* CONFIG_ALLOCSTATS */ + unsigned long __initdata nr_kernel_pages; unsigned long __initdata nr_all_pages; @@ -675,6 +680,9 @@ fallback_buddy_reserve(int start_allocty set_pageblock_type(zone, page, reserve_type); inc_reserve_count(zone, reserve_type); + inc_kernnorclm_full_steal(zone); + } else { + inc_kernnorclm_partial_steal(zone); } return area; } @@ -714,6 +722,15 @@ fallback_alloc(int alloctype, struct zon current_order, area); } + + /* + * If the current alloctype is RCLM_FALLBACK, it means + * that the requested pool and fallback pool are both + * depleted and we are falling back to other pools. + * At this point, pools are starting to get fragmented + */ + if (alloctype == RCLM_FALLBACK) + inc_fallback_count(zone, start_alloctype); } return NULL; @@ -730,6 +747,8 @@ static struct page *__rmqueue(struct zon unsigned int current_order; struct page *page; + inc_alloc_count(zone, alloctype); + for (current_order = order; current_order < MAX_ORDER; ++current_order) { area = &(zone->free_area_lists[alloctype][current_order]); if (list_empty(&area->free_list)) @@ -2319,6 +2338,20 @@ static void __init free_area_init_core(s zone_start_pfn += size; zone_init_free_lists(pgdat, zone, zone->spanned_pages); + +#ifdef CONFIG_ALLOCSTAT + memset((unsigned long *)zone->fallback_count, 0, + sizeof(zone->fallback_count)); + memset((unsigned long *)zone->alloc_count, 0, + sizeof(zone->alloc_count)); + memset((unsigned long *)zone->alloc_count, 0, + sizeof(zone->alloc_count)); + zone->kernnorclm_partial_steal=0; + zone->kernnorclm_full_steal=0; + zone->reserve_count[RCLM_NORCLM] = + realsize >> (MAX_ORDER-1); +#endif + } } @@ -2415,6 +2448,18 @@ static int frag_show(struct seq_file *m, int order, type; struct free_area *area; unsigned long nr_bufs = 0; +#ifdef CONFIG_ALLOCSTATS + int i; + unsigned long kernnorclm_full_steal=0; + unsigned long kernnorclm_partial_steal=0; + unsigned long reserve_count[RCLM_TYPES]; + unsigned long fallback_count[RCLM_TYPES]; + unsigned long alloc_count[RCLM_TYPES]; + + memset(reserve_count, 0, sizeof(reserve_count)); + memset(fallback_count, 0, sizeof(fallback_count)); + memset(alloc_count, 0, sizeof(alloc_count)); +#endif for (zone = node_zones; zone - node_zones < MAX_NR_ZONES; ++zone) { if (!zone->present_pages) @@ -2435,6 +2480,79 @@ static int frag_show(struct seq_file *m, spin_unlock_irqrestore(&zone->lock, flags); seq_putc(m, '\n'); } + +#ifdef CONFIG_ALLOCSTATS + /* Show statistics for each allocation type */ + seq_printf(m, "\nPer-allocation-type statistics"); + for (zone = node_zones; zone - node_zones < MAX_NR_ZONES; ++zone) { + if (!zone->present_pages) + continue; + + spin_lock_irqsave(&zone->lock, flags); + for (type=0; type < RCLM_TYPES; type++) { + struct list_head *elem; + seq_printf(m, "\nNode %d, zone %8s, type %10s ", + pgdat->node_id, zone->name, + type_names[type]); + for (order = 0; order < MAX_ORDER; ++order) { + nr_bufs = 0; + + list_for_each(elem, &(zone->free_area_lists[type][order].free_list)) + ++nr_bufs; + seq_printf(m, "%6lu ", nr_bufs); + } + } + + /* Scan global list */ + seq_printf(m, "\n"); + seq_printf(m, "Node %d, zone %8s, type %10s", + pgdat->node_id, zone->name, + "MAX_ORDER"); + nr_bufs = 0; + for (type=0; type < RCLM_TYPES; type++) { + nr_bufs += zone->free_area_lists[type][MAX_ORDER-1].nr_free; + } + seq_printf(m, "%6lu ", nr_bufs); + seq_printf(m, "\n"); + + seq_printf(m, "%s Zone beancounters\n", zone->name); + seq_printf(m, "Fallback balance: %d\n", (int)zone->fallback_balance); + seq_printf(m, "Fallback reserve: %d\n", (int)zone->fallback_reserve); + seq_printf(m, "Partial steal: %lu\n", zone->kernnorclm_partial_steal); + seq_printf(m, "Full steal: %lu\n", zone->kernnorclm_full_steal); + + kernnorclm_partial_steal += zone->kernnorclm_partial_steal; + kernnorclm_full_steal += zone->kernnorclm_full_steal; + seq_putc(m, '\n'); + + for (i=0; i< RCLM_TYPES; i++) { + seq_printf(m, "%-10s Allocs: %-10lu Reserve: %-10lu Fallbacks: %-10lu\n", + type_names[i], + zone->alloc_count[i], + zone->reserve_count[i], + zone->fallback_count[i]); + alloc_count[i] += zone->alloc_count[i]; + reserve_count[i] += zone->reserve_count[i]; + fallback_count[i] += zone->fallback_count[i]; + } + + spin_unlock_irqrestore(&zone->lock, flags); + } + + + /* Show bean counters */ + seq_printf(m, "\nGlobal beancounters\n"); + seq_printf(m, "Partial steal: %lu\n", kernnorclm_partial_steal); + seq_printf(m, "Full steal: %lu\n", kernnorclm_full_steal); + + for (i=0; i< RCLM_TYPES; i++) { + seq_printf(m, "%-10s Allocs: %-10lu Reserve: %-10lu Fallbacks: %-10lu\n", + type_names[i], + alloc_count[i], + reserve_count[i], + fallback_count[i]); + } +#endif /* CONFIG_ALLOCSTATS */ return 0; } -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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