Script Performance Tests

We conducted performance tests for all aspects of our scripts.
For this purpose, we developed an benchmark subproject with JMH that computes the complexity of scripts after compilation phase by AST (Abstract Syntax Tree) traversal in special complexity units.

Complexity units is a measure of the script's relative cost: we found out the most expensive operation in terms of computational complexity and defined it equal to 100 complexity units. In every test, we conducted 10 tests and calculated the average cost.

The performance tests' results are the following:

Environment Functions Benchmark

Functions used in the script that do not refer to the state:

Benchmark	Score	Error
addressFromPublicKey	15,457.000 ns/op	± 1,551.809 ns/op
addressFromString_full	28,437.102 ns/op	± 706.255 ns/op
base58_26_encode	2,207.600 ns/op	± 34.466 ns/op
base58_decode_full	18,645.203 ns/op	± 415.800 ns/op
base58_encode	12,243.466 ns/op	± 197.687 ns/op
blake2b256	7,991.033 ns/op	± 438.591 ns/op
curve25519_full	628,001.764 ns/op	± 35,875.443 ns/op
curve25519_generateKeypair	95,835.192 ns/op	± 4,453.657 ns/op
curve25519_sign_full	303,429.901 ns/op	± 6,683.234 ns/op
keccak256	27,588.387 ns/op	± 1,002.837 ns/op
random_bytes_500	1,188.761 ns/op	± 41.945 ns/op
secureHash	10,292.214 ns/op	± 233.883 ns/op
sha256	3,633.718 ns/op	± 142.837 ns/op

Where:

• The _full suffix means that we create an array of N random bytes, then we either code it and decode it, or we sign it and check it.
• base58_26_encode - the test for 26 bytes.
• base58_decode_full,base58_encode - tests for 64 bytes.
• curve25519_sign_full, curve25519_full - tests for 512 bytes.

Waves Environment Benchmark

Functions used in the script that refer to the state:

Benchmark	Score	Error
accountBalanceOf_asset	10,887.166 ns/op	± 490.024 ns/op
accountBalanceOf_waves	12,837.177 ns/op	± 46.377 ns/op
data	12,154.862 ns/op	± 666.479 ns/op
resolveAddress	7,925.741 ns/op	± 114.994 ns/op
transactionById	70,485.131 ns/op	± 3,587.244 ns/op
transactionHeightById	66,644.724 ns/op	± 1,663.940 ns/op

Language Serde Benchmark

Processes of serialization and deserialization of the script:

Benchmark	Score	Error
serialize	572,441.780 ns/op	± 241,711.329 ns/op
deserialize	492,556.077 ns/op	± 46,122.237 ns/op

Script Estimator Benchmark

In this test, we used a script, which size is about 1 kB. It contains sums of 100 numbers and one comparison operation. Here the script's complexity computation is presented:

Benchmark	Score	Error
apply	130,286.995 ns/op	± 3,544.940 ns/op

Script Evaluator Benchmark

The execution time of the script described in the previous section:

Benchmark	Score	Error
apply	172,482.796 ns/op	± 4,170.202 ns/op

State Synthetic Benchmark

Let's Compare the applying process for a block with 5,000 tx for a scripted account and for regular one:

Benchmark	Score	Error
appendBlock_smart	2,861.589 ms/op	± 108.005 ms/op
appendBlock	2,069.613 ms/op	± 449.040 ms/op

Final Results

The most expensive functions are:

• base58
• sigVerify

As a result, we define the following constraint for a script cost: a script must have a size of** no more then 8 kB** and it must be faster than 20 executions of sigVerify, which is the most expensive operation.
The fixed fee for each scripted unit is equal to 400,000 wavelets (Waves coins, 100,000,000 wavelets = 1 Wave).
For example, if you use a scripted asset (smart asset) then you pay 400,000 wavelets, if you also have a scripted transaction then you have to pay 2 * 400,000 wavelets.