diff options
| author | Prakash Surya <[email protected]> | 2013-07-10 15:53:48 -0700 |
|---|---|---|
| committer | Brian Behlendorf <[email protected]> | 2013-07-11 13:53:44 -0700 |
| commit | 92334b14ec378b1693573b52c09816bbade9cf3e (patch) | |
| tree | 2ea0e48d7f7bef661756633ae34d68acc514c71b /include | |
| parent | bf89c19914c66b030333460952dbdfabf9ff527e (diff) | |
Add new kstat for monitoring time in dmu_tx_assign
This change adds a new kstat to gain some visibility into the amount of
time spent in each call to dmu_tx_assign. A histogram is exported via
a new dmu_tx_assign_histogram-$POOLNAME file. The information contained
in this histogram is the frequency dmu_tx_assign took to complete given
an interval range. For example, given the below histogram file:
$ cat /proc/spl/kstat/zfs/dmu_tx_assign_histogram-tank
12 1 0x01 32 1536 19792068076691 20516481514522
name type data
1 us 4 859
2 us 4 252
4 us 4 171
8 us 4 2
16 us 4 0
32 us 4 2
64 us 4 0
128 us 4 0
256 us 4 0
512 us 4 0
1024 us 4 0
2048 us 4 0
4096 us 4 0
8192 us 4 0
16384 us 4 0
32768 us 4 1
65536 us 4 1
131072 us 4 1
262144 us 4 4
524288 us 4 0
1048576 us 4 0
2097152 us 4 0
4194304 us 4 0
8388608 us 4 0
16777216 us 4 0
33554432 us 4 0
67108864 us 4 0
134217728 us 4 0
268435456 us 4 0
536870912 us 4 0
1073741824 us 4 0
2147483648 us 4 0
one can see most calls to dmu_tx_assign completed in 32us or less, but a
few outliers did not. Specifically, 4 of the calls took between 262144us
and 131072us. This information is difficult, if not impossible, to gather
without this change.
Signed-off-by: Prakash Surya <[email protected]>
Signed-off-by: Brian Behlendorf <[email protected]>
Closes #1584
Diffstat (limited to 'include')
| -rw-r--r-- | include/sys/dsl_pool.h | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/include/sys/dsl_pool.h b/include/sys/dsl_pool.h index f4de774e4..4a4bf76ef 100644 --- a/include/sys/dsl_pool.h +++ b/include/sys/dsl_pool.h @@ -89,6 +89,7 @@ typedef struct dsl_pool { uint64_t dp_root_dir_obj; struct taskq *dp_iput_taskq; kstat_t *dp_txg_kstat; + kstat_t *dp_tx_assign_kstat; /* No lock needed - sync context only */ blkptr_t dp_meta_rootbp; @@ -111,6 +112,8 @@ typedef struct dsl_pool { uint64_t dp_mos_uncompressed_delta; uint64_t dp_txg_history_size; list_t dp_txg_history; + uint64_t dp_tx_assign_size; + kstat_named_t *dp_tx_assign_buckets; /* Has its own locking */ @@ -162,6 +165,8 @@ extern int dsl_pool_user_release(dsl_pool_t *dp, uint64_t dsobj, extern void dsl_pool_clean_tmp_userrefs(dsl_pool_t *dp); int dsl_pool_open_special_dir(dsl_pool_t *dp, const char *name, dsl_dir_t **); +void dsl_pool_tx_assign_add_usecs(dsl_pool_t *dp, uint64_t usecs); + txg_history_t *dsl_pool_txg_history_add(dsl_pool_t *dp, uint64_t txg); txg_history_t *dsl_pool_txg_history_get(dsl_pool_t *dp, uint64_t txg); void dsl_pool_txg_history_put(txg_history_t *th); |