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| author | Divyesh Shah <dpshah@google.com> | 2010-04-08 21:15:10 -0700 |
|---|---|---|
| committer | Jens Axboe <jens.axboe@oracle.com> | 2010-04-09 08:36:08 +0200 |
| commit | cdc1184cf4a7bd99f5473a91244197accc49146b (patch) | |
| tree | ecd572867bfa5a82fa4ed16d7303448c7ea7d24c /block/blk-cgroup.h | |
| parent | 812d402648f4fc1ab1091b2172a46fc1b367c724 (diff) | |
| download | linux-cdc1184cf4a7bd99f5473a91244197accc49146b.tar.bz2 | |
blkio: Add io_queued and avg_queue_size stats
These stats are useful for getting a feel for the queue depth of the cgroup,
i.e., how filled up its queues are at a given instant and over the existence of
the cgroup. This ability is useful when debugging problems in the wild as it
helps understand the application's IO pattern w/o having to read through the
userspace code (coz its tedious or just not available) or w/o the ability
to run blktrace (since you may not have root access and/or not want to disturb
performance).
Signed-off-by: Divyesh Shah<dpshah@google.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Diffstat (limited to 'block/blk-cgroup.h')
| -rw-r--r-- | block/blk-cgroup.h | 20 |
1 files changed, 19 insertions, 1 deletions
diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h index 470a29db6bec..bea7f3b9a88e 100644 --- a/block/blk-cgroup.h +++ b/block/blk-cgroup.h @@ -36,10 +36,13 @@ enum stat_type { BLKIO_STAT_WAIT_TIME, /* Number of IOs merged */ BLKIO_STAT_MERGED, + /* Number of IOs queued up */ + BLKIO_STAT_QUEUED, /* All the single valued stats go below this */ BLKIO_STAT_TIME, BLKIO_STAT_SECTORS, #ifdef CONFIG_DEBUG_BLK_CGROUP + BLKIO_STAT_AVG_QUEUE_SIZE, BLKIO_STAT_DEQUEUE #endif }; @@ -63,8 +66,12 @@ struct blkio_group_stats { /* total disk time and nr sectors dispatched by this group */ uint64_t time; uint64_t sectors; - uint64_t stat_arr[BLKIO_STAT_MERGED + 1][BLKIO_STAT_TOTAL]; + uint64_t stat_arr[BLKIO_STAT_QUEUED + 1][BLKIO_STAT_TOTAL]; #ifdef CONFIG_DEBUG_BLK_CGROUP + /* Sum of number of IOs queued across all samples */ + uint64_t avg_queue_size_sum; + /* Count of samples taken for average */ + uint64_t avg_queue_size_samples; /* How many times this group has been removed from service tree */ unsigned long dequeue; #endif @@ -127,10 +134,13 @@ static inline char *blkg_path(struct blkio_group *blkg) { return blkg->path; } +void blkiocg_update_set_active_queue_stats(struct blkio_group *blkg); void blkiocg_update_dequeue_stats(struct blkio_group *blkg, unsigned long dequeue); #else static inline char *blkg_path(struct blkio_group *blkg) { return NULL; } +static inline void blkiocg_update_set_active_queue_stats( + struct blkio_group *blkg) {} static inline void blkiocg_update_dequeue_stats(struct blkio_group *blkg, unsigned long dequeue) {} #endif @@ -152,6 +162,10 @@ void blkiocg_update_completion_stats(struct blkio_group *blkg, uint64_t start_time, uint64_t io_start_time, bool direction, bool sync); void blkiocg_update_io_merged_stats(struct blkio_group *blkg, bool direction, bool sync); +void blkiocg_update_request_add_stats(struct blkio_group *blkg, + struct blkio_group *curr_blkg, bool direction, bool sync); +void blkiocg_update_request_remove_stats(struct blkio_group *blkg, + bool direction, bool sync); #else struct cgroup; static inline struct blkio_cgroup * @@ -175,5 +189,9 @@ static inline void blkiocg_update_completion_stats(struct blkio_group *blkg, bool sync) {} static inline void blkiocg_update_io_merged_stats(struct blkio_group *blkg, bool direction, bool sync) {} +static inline void blkiocg_update_request_add_stats(struct blkio_group *blkg, + struct blkio_group *curr_blkg, bool direction, bool sync) {} +static inline void blkiocg_update_request_remove_stats(struct blkio_group *blkg, + bool direction, bool sync) {} #endif #endif /* _BLK_CGROUP_H */ |