5.2 stat file
-5.2.1 memory.stat file includes following statistics
+memory.stat file includes following statistics
# per-memory cgroup local status
cache - # of bytes of page cache memory.
file_mapped is accounted only when the memory cgroup is owner of page
cache.)
-5.2.2 memory.vmscan_stat
-
-memory.vmscan_stat includes statistics information for memory scanning and
-freeing, reclaiming. The statistics shows memory scanning information since
-memory cgroup creation and can be reset to 0 by writing 0 as
-
- #echo 0 > ../memory.vmscan_stat
-
-This file contains following statistics.
-
-[param]_[file_or_anon]_pages_by_[reason]_[under_heararchy]
-[param]_elapsed_ns_by_[reason]_[under_hierarchy]
-
-For example,
-
- scanned_file_pages_by_limit indicates the number of scanned
- file pages at vmscan.
-
-Now, 3 parameters are supported
-
- scanned - the number of pages scanned by vmscan
- rotated - the number of pages activated at vmscan
- freed - the number of pages freed by vmscan
-
-If "rotated" is high against scanned/freed, the memcg seems busy.
-
-Now, 2 reason are supported
-
- limit - the memory cgroup's limit
- system - global memory pressure + softlimit
- (global memory pressure not under softlimit is not handled now)
-
-When under_hierarchy is added in the tail, the number indicates the
-total memcg scan of its children and itself.
-
-elapsed_ns is a elapsed time in nanosecond. This may include sleep time
-and not indicates CPU usage. So, please take this as just showing
-latency.
-
-Here is an example.
-
-# cat /cgroup/memory/A/memory.vmscan_stat
-scanned_pages_by_limit 9471864
-scanned_anon_pages_by_limit 6640629
-scanned_file_pages_by_limit 2831235
-rotated_pages_by_limit 4243974
-rotated_anon_pages_by_limit 3971968
-rotated_file_pages_by_limit 272006
-freed_pages_by_limit 2318492
-freed_anon_pages_by_limit 962052
-freed_file_pages_by_limit 1356440
-elapsed_ns_by_limit 351386416101
-scanned_pages_by_system 0
-scanned_anon_pages_by_system 0
-scanned_file_pages_by_system 0
-rotated_pages_by_system 0
-rotated_anon_pages_by_system 0
-rotated_file_pages_by_system 0
-freed_pages_by_system 0
-freed_anon_pages_by_system 0
-freed_file_pages_by_system 0
-elapsed_ns_by_system 0
-scanned_pages_by_limit_under_hierarchy 9471864
-scanned_anon_pages_by_limit_under_hierarchy 6640629
-scanned_file_pages_by_limit_under_hierarchy 2831235
-rotated_pages_by_limit_under_hierarchy 4243974
-rotated_anon_pages_by_limit_under_hierarchy 3971968
-rotated_file_pages_by_limit_under_hierarchy 272006
-freed_pages_by_limit_under_hierarchy 2318492
-freed_anon_pages_by_limit_under_hierarchy 962052
-freed_file_pages_by_limit_under_hierarchy 1356440
-elapsed_ns_by_limit_under_hierarchy 351386416101
-scanned_pages_by_system_under_hierarchy 0
-scanned_anon_pages_by_system_under_hierarchy 0
-scanned_file_pages_by_system_under_hierarchy 0
-rotated_pages_by_system_under_hierarchy 0
-rotated_anon_pages_by_system_under_hierarchy 0
-rotated_file_pages_by_system_under_hierarchy 0
-freed_pages_by_system_under_hierarchy 0
-freed_anon_pages_by_system_under_hierarchy 0
-freed_file_pages_by_system_under_hierarchy 0
-elapsed_ns_by_system_under_hierarchy 0
-
5.3 swappiness
Similar to /proc/sys/vm/swappiness, but affecting a hierarchy of groups only.
struct mem_cgroup *mem_cont,
int active, int file);
-struct memcg_scanrecord {
- struct mem_cgroup *mem; /* scanend memory cgroup */
- struct mem_cgroup *root; /* scan target hierarchy root */
- int context; /* scanning context (see memcontrol.c) */
- unsigned long nr_scanned[2]; /* the number of scanned pages */
- unsigned long nr_rotated[2]; /* the number of rotated pages */
- unsigned long nr_freed[2]; /* the number of freed pages */
- unsigned long elapsed; /* nsec of time elapsed while scanning */
-};
-
#ifdef CONFIG_CGROUP_MEM_RES_CTLR
/*
* All "charge" functions with gfp_mask should use GFP_KERNEL or
extern void mem_cgroup_print_oom_info(struct mem_cgroup *memcg,
struct task_struct *p);
-extern unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *mem,
- gfp_t gfp_mask, bool noswap,
- struct memcg_scanrecord *rec);
-extern unsigned long mem_cgroup_shrink_node_zone(struct mem_cgroup *mem,
- gfp_t gfp_mask, bool noswap,
- struct zone *zone,
- struct memcg_scanrecord *rec,
- unsigned long *nr_scanned);
-
#ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
extern int do_swap_account;
#endif
extern unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
gfp_t gfp_mask, nodemask_t *mask);
extern int __isolate_lru_page(struct page *page, int mode, int file);
+extern unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *mem,
+ gfp_t gfp_mask, bool noswap);
+extern unsigned long mem_cgroup_shrink_node_zone(struct mem_cgroup *mem,
+ gfp_t gfp_mask, bool noswap,
+ struct zone *zone,
+ unsigned long *nr_scanned);
extern unsigned long shrink_all_memory(unsigned long nr_pages);
extern int vm_swappiness;
extern int remove_mapping(struct address_space *mapping, struct page *page);
static void mem_cgroup_threshold(struct mem_cgroup *mem);
static void mem_cgroup_oom_notify(struct mem_cgroup *mem);
-enum {
- SCAN_BY_LIMIT,
- SCAN_BY_SYSTEM,
- NR_SCAN_CONTEXT,
- SCAN_BY_SHRINK, /* not recorded now */
-};
-
-enum {
- SCAN,
- SCAN_ANON,
- SCAN_FILE,
- ROTATE,
- ROTATE_ANON,
- ROTATE_FILE,
- FREED,
- FREED_ANON,
- FREED_FILE,
- ELAPSED,
- NR_SCANSTATS,
-};
-
-struct scanstat {
- spinlock_t lock;
- unsigned long stats[NR_SCAN_CONTEXT][NR_SCANSTATS];
- unsigned long rootstats[NR_SCAN_CONTEXT][NR_SCANSTATS];
-};
-
-const char *scanstat_string[NR_SCANSTATS] = {
- "scanned_pages",
- "scanned_anon_pages",
- "scanned_file_pages",
- "rotated_pages",
- "rotated_anon_pages",
- "rotated_file_pages",
- "freed_pages",
- "freed_anon_pages",
- "freed_file_pages",
- "elapsed_ns",
-};
-#define SCANSTAT_WORD_LIMIT "_by_limit"
-#define SCANSTAT_WORD_SYSTEM "_by_system"
-#define SCANSTAT_WORD_HIERARCHY "_under_hierarchy"
-
-
/*
* The memory controller data structure. The memory controller controls both
* page cache and RSS per cgroup. We would eventually like to provide
/* For oom notifier event fd */
struct list_head oom_notify;
- /* For recording LRU-scan statistics */
- struct scanstat scanstat;
+
/*
* Should we move charges of a task when a task is moved into this
* mem_cgroup ? And what type of charges should we move ?
}
#endif
-static void __mem_cgroup_record_scanstat(unsigned long *stats,
- struct memcg_scanrecord *rec)
-{
-
- stats[SCAN] += rec->nr_scanned[0] + rec->nr_scanned[1];
- stats[SCAN_ANON] += rec->nr_scanned[0];
- stats[SCAN_FILE] += rec->nr_scanned[1];
-
- stats[ROTATE] += rec->nr_rotated[0] + rec->nr_rotated[1];
- stats[ROTATE_ANON] += rec->nr_rotated[0];
- stats[ROTATE_FILE] += rec->nr_rotated[1];
-
- stats[FREED] += rec->nr_freed[0] + rec->nr_freed[1];
- stats[FREED_ANON] += rec->nr_freed[0];
- stats[FREED_FILE] += rec->nr_freed[1];
-
- stats[ELAPSED] += rec->elapsed;
-}
-
-static void mem_cgroup_record_scanstat(struct memcg_scanrecord *rec)
-{
- struct mem_cgroup *mem;
- int context = rec->context;
-
- if (context >= NR_SCAN_CONTEXT)
- return;
-
- mem = rec->mem;
- spin_lock(&mem->scanstat.lock);
- __mem_cgroup_record_scanstat(mem->scanstat.stats[context], rec);
- spin_unlock(&mem->scanstat.lock);
-
- mem = rec->root;
- spin_lock(&mem->scanstat.lock);
- __mem_cgroup_record_scanstat(mem->scanstat.rootstats[context], rec);
- spin_unlock(&mem->scanstat.lock);
-}
-
/*
* Scan the hierarchy if needed to reclaim memory. We remember the last child
* we reclaimed from, so that we don't end up penalizing one child extensively
bool noswap = reclaim_options & MEM_CGROUP_RECLAIM_NOSWAP;
bool shrink = reclaim_options & MEM_CGROUP_RECLAIM_SHRINK;
bool check_soft = reclaim_options & MEM_CGROUP_RECLAIM_SOFT;
- struct memcg_scanrecord rec;
unsigned long excess;
- unsigned long scanned;
+ unsigned long nr_scanned;
excess = res_counter_soft_limit_excess(&root_mem->res) >> PAGE_SHIFT;
if (!check_soft && !shrink && root_mem->memsw_is_minimum)
noswap = true;
- if (shrink)
- rec.context = SCAN_BY_SHRINK;
- else if (check_soft)
- rec.context = SCAN_BY_SYSTEM;
- else
- rec.context = SCAN_BY_LIMIT;
-
- rec.root = root_mem;
-
while (1) {
victim = mem_cgroup_select_victim(root_mem);
if (victim == root_mem) {
css_put(&victim->css);
continue;
}
- rec.mem = victim;
- rec.nr_scanned[0] = 0;
- rec.nr_scanned[1] = 0;
- rec.nr_rotated[0] = 0;
- rec.nr_rotated[1] = 0;
- rec.nr_freed[0] = 0;
- rec.nr_freed[1] = 0;
- rec.elapsed = 0;
/* we use swappiness of local cgroup */
if (check_soft) {
ret = mem_cgroup_shrink_node_zone(victim, gfp_mask,
- noswap, zone, &rec, &scanned);
- *total_scanned += scanned;
+ noswap, zone, &nr_scanned);
+ *total_scanned += nr_scanned;
} else
ret = try_to_free_mem_cgroup_pages(victim, gfp_mask,
- noswap, &rec);
- mem_cgroup_record_scanstat(&rec);
+ noswap);
css_put(&victim->css);
/*
* At shrinking usage, we can't check we should stop here or
/* try to free all pages in this cgroup */
shrink = 1;
while (nr_retries && mem->res.usage > 0) {
- struct memcg_scanrecord rec;
int progress;
if (signal_pending(current)) {
ret = -EINTR;
goto out;
}
- rec.context = SCAN_BY_SHRINK;
- rec.mem = mem;
- rec.root = mem;
progress = try_to_free_mem_cgroup_pages(mem, GFP_KERNEL,
- false, &rec);
+ false);
if (!progress) {
nr_retries--;
/* maybe some writeback is necessary */
}
#endif /* CONFIG_NUMA */
-static int mem_cgroup_vmscan_stat_read(struct cgroup *cgrp,
- struct cftype *cft,
- struct cgroup_map_cb *cb)
-{
- struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp);
- char string[64];
- int i;
-
- for (i = 0; i < NR_SCANSTATS; i++) {
- strcpy(string, scanstat_string[i]);
- strcat(string, SCANSTAT_WORD_LIMIT);
- cb->fill(cb, string, mem->scanstat.stats[SCAN_BY_LIMIT][i]);
- }
-
- for (i = 0; i < NR_SCANSTATS; i++) {
- strcpy(string, scanstat_string[i]);
- strcat(string, SCANSTAT_WORD_SYSTEM);
- cb->fill(cb, string, mem->scanstat.stats[SCAN_BY_SYSTEM][i]);
- }
-
- for (i = 0; i < NR_SCANSTATS; i++) {
- strcpy(string, scanstat_string[i]);
- strcat(string, SCANSTAT_WORD_LIMIT);
- strcat(string, SCANSTAT_WORD_HIERARCHY);
- cb->fill(cb, string, mem->scanstat.rootstats[SCAN_BY_LIMIT][i]);
- }
- for (i = 0; i < NR_SCANSTATS; i++) {
- strcpy(string, scanstat_string[i]);
- strcat(string, SCANSTAT_WORD_SYSTEM);
- strcat(string, SCANSTAT_WORD_HIERARCHY);
- cb->fill(cb, string, mem->scanstat.rootstats[SCAN_BY_SYSTEM][i]);
- }
- return 0;
-}
-
-static int mem_cgroup_reset_vmscan_stat(struct cgroup *cgrp,
- unsigned int event)
-{
- struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp);
-
- spin_lock(&mem->scanstat.lock);
- memset(&mem->scanstat.stats, 0, sizeof(mem->scanstat.stats));
- memset(&mem->scanstat.rootstats, 0, sizeof(mem->scanstat.rootstats));
- spin_unlock(&mem->scanstat.lock);
- return 0;
-}
-
-
static struct cftype mem_cgroup_files[] = {
{
.name = "usage_in_bytes",
.mode = S_IRUGO,
},
#endif
- {
- .name = "vmscan_stat",
- .read_map = mem_cgroup_vmscan_stat_read,
- .trigger = mem_cgroup_reset_vmscan_stat,
- },
};
#ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
atomic_set(&mem->refcnt, 1);
mem->move_charge_at_immigrate = 0;
mutex_init(&mem->thresholds_lock);
- spin_lock_init(&mem->scanstat.lock);
return &mem->css;
free_out:
__mem_cgroup_free(mem);
/* Which cgroup do we reclaim from */
struct mem_cgroup *mem_cgroup;
- struct memcg_scanrecord *memcg_record;
/*
* Nodemask of nodes allowed by the caller. If NULL, all nodes
int file = is_file_lru(lru);
int numpages = hpage_nr_pages(page);
reclaim_stat->recent_rotated[file] += numpages;
- if (!scanning_global_lru(sc))
- sc->memcg_record->nr_rotated[file] += numpages;
}
if (!pagevec_add(&pvec, page)) {
spin_unlock_irq(&zone->lru_lock);
reclaim_stat->recent_scanned[0] += *nr_anon;
reclaim_stat->recent_scanned[1] += *nr_file;
- if (!scanning_global_lru(sc)) {
- sc->memcg_record->nr_scanned[0] += *nr_anon;
- sc->memcg_record->nr_scanned[1] += *nr_file;
- }
}
/*
nr_reclaimed += shrink_page_list(&page_list, zone, sc);
}
- if (!scanning_global_lru(sc))
- sc->memcg_record->nr_freed[file] += nr_reclaimed;
-
local_irq_disable();
if (current_is_kswapd())
__count_vm_events(KSWAPD_STEAL, nr_reclaimed);
}
reclaim_stat->recent_scanned[file] += nr_taken;
- if (!scanning_global_lru(sc))
- sc->memcg_record->nr_scanned[file] += nr_taken;
__count_zone_vm_events(PGREFILL, zone, pgscanned);
if (file)
* get_scan_ratio.
*/
reclaim_stat->recent_rotated[file] += nr_rotated;
- if (!scanning_global_lru(sc))
- sc->memcg_record->nr_rotated[file] += nr_rotated;
move_active_pages_to_lru(zone, &l_active,
LRU_ACTIVE + file * LRU_FILE);
#ifdef CONFIG_CGROUP_MEM_RES_CTLR
unsigned long mem_cgroup_shrink_node_zone(struct mem_cgroup *mem,
- gfp_t gfp_mask, bool noswap,
- struct zone *zone,
- struct memcg_scanrecord *rec,
- unsigned long *scanned)
+ gfp_t gfp_mask, bool noswap,
+ struct zone *zone,
+ unsigned long *nr_scanned)
{
struct scan_control sc = {
.nr_scanned = 0,
.may_swap = !noswap,
.order = 0,
.mem_cgroup = mem,
- .memcg_record = rec,
};
- ktime_t start, end;
sc.gfp_mask = (gfp_mask & GFP_RECLAIM_MASK) |
(GFP_HIGHUSER_MOVABLE & ~GFP_RECLAIM_MASK);
sc.may_writepage,
sc.gfp_mask);
- start = ktime_get();
/*
* NOTE: Although we can get the priority field, using it
* here is not a good idea, since it limits the pages we can scan.
* the priority and make it zero.
*/
shrink_zone(0, zone, &sc);
- end = ktime_get();
-
- if (rec)
- rec->elapsed += ktime_to_ns(ktime_sub(end, start));
- *scanned = sc.nr_scanned;
trace_mm_vmscan_memcg_softlimit_reclaim_end(sc.nr_reclaimed);
+ *nr_scanned = sc.nr_scanned;
return sc.nr_reclaimed;
}
unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *mem_cont,
gfp_t gfp_mask,
- bool noswap,
- struct memcg_scanrecord *rec)
+ bool noswap)
{
struct zonelist *zonelist;
unsigned long nr_reclaimed;
- ktime_t start, end;
int nid;
struct scan_control sc = {
.may_writepage = !laptop_mode,
.nr_to_reclaim = SWAP_CLUSTER_MAX,
.order = 0,
.mem_cgroup = mem_cont,
- .memcg_record = rec,
.nodemask = NULL, /* we don't care the placement */
.gfp_mask = (gfp_mask & GFP_RECLAIM_MASK) |
(GFP_HIGHUSER_MOVABLE & ~GFP_RECLAIM_MASK),
.gfp_mask = sc.gfp_mask,
};
- start = ktime_get();
/*
* Unlike direct reclaim via alloc_pages(), memcg's reclaim doesn't
* take care of from where we get pages. So the node where we start the
sc.gfp_mask);
nr_reclaimed = do_try_to_free_pages(zonelist, &sc, &shrink);
- end = ktime_get();
- if (rec)
- rec->elapsed += ktime_to_ns(ktime_sub(end, start));
trace_mm_vmscan_memcg_reclaim_end(nr_reclaimed);