Be aware that this tool is a per-node, per-bucket operation. That means that if you want to perform this operation, you must specify the IP address of a node in the cluster and a named bucket. If you do not provided a named bucket, the server will apply the setting to any default bucket that exists at the specified node. If you want to perform this operation for an entire cluster, you will need to perform the command for every node/bucket combination that exists for that cluster.
The following is sample output from cbstats
timings:
disk_insert (10008 total) 8us - 16us : ( 94.80%)8 ########################################### 16us - 32us : ( 97.70%) 290 # 32us - 64us : ( 98.43%) 73 64us - 128us : ( 99.29%) 86 128us - 256us : ( 99.77%) 48 256us - 512us : ( 99.79%) 2 512us - 1ms : ( 99.91%) 12 1ms - 2ms : ( 99.92%) 1 disk_commit (1 total) 0 - 1s : (100.00%) 1 ############################################################# disk_vbstate_snapshot (2 total) 4s - 8s : (100.00%) 2 ############################################################# get_stats_cmd (1535 total) .... set_vb_cmd (1024 total) 4us - 8us : ( 97.95%) 1003 ######################################################## 8us - 16us : ( 98.83%) 9 ....
The first statistic tells you that
disk_insert took 8-16µs8 times, 16-32µs 290
times, and so forth.
The following are the possible return values provided by
cbstats timings. The return values provided
by this command depend on what has actually occurred on a data
bucket:
bg_load | Background fetches waiting for disk |
bg_wait | Background fetches waiting in the dispatcher queue |
data_age | Age of data written to disk |
disk_commit | Time waiting for a commit after a batch of updates |
disk_del | Wait for disk to delete an item |
disk_insert | Wait for disk to store a new item |
disk_vbstate_snapshot | Time spent persisting vbucket state changes |
disk_update | Wait time for disk to modify an existing item |
get_cmd | Servicing get requests |
get_stats_cmd | Servicing get_stats requests |
set_vb_cmd | Servicing vbucket set state commands |
item_alloc_sizes | Item allocation size counters (in bytes) |
notify_io | Time for waking blocked connections |
set_vb_cmd | Servicing vbucket set state commands |
storage_age | Time since most recently persisted item was initially queued for storage. |
tap_mutation | Time spent servicing tap mutations |