How to set zero lookup rate?

[WangTingZheng]

The meaning of "zero look rate" is the proportion of keys in queries that are not present in the database during the query process, Some paper, such as Elasticbf need this.

[ls4154]

Since YCSB performs transactions (update, read) only for already inserted keys, zero lookup is not supported. But it can be achieved by using a higher recordcount in the run phase than recordcount used in the load phase.

For example, if you load with recordcount=10000 and do the run phase with recordcount=20000, the zero lookup rate will be 50%.

$ ./ycsb -load -db leveldb -P workloads/workloada -P leveldb/leveldb.properties -p recordcount=10000 -p threadcount=1 -s
2023-08-19 18:15:54 0 sec: 0 operations;
2023-08-19 18:15:54 0 sec: 10000 operations; [INSERT: Count=10000 Max=40.29 Min=1.71 Avg=3.33 90=5.21 99=7.56 99.9=19.63 99.99=28.93]
Load runtime(sec): 0.212605
Load operations(ops): 10000
Load throughput(ops/sec): 47035.5

$ ./ycsb -run -db leveldb -P workloads/workloada -P leveldb/leveldb.properties -p recordcount=20000 -p threadcount=1 -s
2023-08-19 18:16:03 0 sec: 0 operations;
2023-08-19 18:16:03 0 sec: 10000 operations; 
[READ: Count=2490 Max=49.25 Min=2.47 Avg=3.63 90=4.09 99=6.46 99.9=10.21 99.99=49.25] 
[UPDATE: Count=2415 Max=35.84 Min=4.56 Avg=6.29 90=7.29 99=9.54 99.9=23.41 99.99=35.84] 
[READ-FAILED: Count=2506 Max=15.86 Min=0.29 Avg=0.91 90=1.06 99=1.35 99.9=1.77 99.99=15.86]
[UPDATE-FAILED: Count=2589 Max=24.13 Min=0.56 Avg=0.93 90=1.06 99=1.32 99.9=3.59 99.99=24.13]
Run runtime(sec): 0.128209
Run operations(ops): 10000
Run throughput(ops/sec): 77997.9

Adding that feature might not be difficult. However, from what I have read, the elasticbf paper simply presents zero lookup ratio. In order to implement it, we need information about the distribution of non-existent keys.

[ls4154]

Closed due to inactivity.