You may find this information useful for measuring your node and cluster. This command returns the time required for operations to complete. All times are provided in milliseconds:

./cbstats 10.4.2.5:11210 timings

Couchbase Server returns a histogram showing total operations, and then detail about operations that completed within different time intervals:

(1 total)
    0 - 1us       : (100.00%) 1 ##################################################
 disk_invalid_vbtable_del (1 total)
    1ms - 2ms     : (100.00%) 1 ##################################################
 get_stats_cmd (3702 total)
    0 - 1us       : (  0.05%)   2 
    1us - 2us     : (  4.73%) 173 ##
    2us - 4us     : ( 29.58%) 920 ###########
    4us - 8us     : ( 30.90%)  49 
    8us - 16us    : ( 31.06%)   6 
    32us - 64us   : ( 31.58%)  19 
    64us - 128us  : ( 40.46%) 329 ####
    128us - 256us : ( 55.73%) 565 #######
    256us - 512us : ( 60.37%) 172 ##
    512us - 1ms   : ( 72.42%) 446 #####
    1ms - 2ms     : ( 82.66%) 379 ####
    2ms - 4ms     : ( 98.54%) 588 #######
    4ms - 8ms     : ( 99.95%)  52 
    8ms - 16ms    : (100.00%)   2 
 set_vb_cmd (1024 total)
    8us - 16us    : (  0.49%)   5 
    16us - 32us   : ( 76.56%) 779 ####################################
    32us - 64us   : ( 98.83%) 228 ##########
    64us - 128us  : (100.00%)  12