Oh, I see--thanks for the tip; I wasn't aware of the SET RUNS feature, which is really helpful! With 1000 runs, the average execution time is more in line with expectations: 38.96ms for expression #1 and 12.44ms for #2. But I notice that with successive executions, #1 gets faster: 38.96ms, 17.73ms, 12.82ms. Is this a result of caching?

Best,

Tim

--
Tim A. Thompson (he, him)
Librarian for Applied Metadata Research
Yale University Library

On Wed, Apr 27, 2022 at 5:09 PM Christian Grün <christian.gruen@gmail.com> wrote:

2. Direct lookup against subindex
Time: 3.3ms
Expression: ft:search($index, $text)/../..

3. Lookup against subindex file with reference to large index
Time: 2.9ms
Expression:
let $s :=
ft:search($index, $text)/../..
return db:open-id($db, $s/id)/../..

My question is: why would the third expression be slightly faster (or at least not slower) than the second one, if it involves additional computation?

I assume it's due to slight variations during your measurements. How many items will be returned by ft:search? Do you get the same runtime if you run the code 100 or 1000 times?

In the GUI, you can type and execute SET RUNS 100 in the top input bar (in command mode). Your query will then be executed multiple times, and you will get shown the average runtime in the Info View.