simple-lru-cache differences between node v10 & node v12

[Yomguithereal]

On my computer (Macbook 2013), the simple-lru-cache library's results vary greatly between node v10:

name	set	get1	update	get2	evict
hashlru	15198	15456	14782	16515	7806
mnemonist-object	11280	58140	36298	60060	7339
quick-lru	7468	3980	5598	3958	5700
tiny-lru	5536	30211	26596	35461	5469
lru-fast	5585	30488	33223	30166	5094
mnemonist-map	5593	12151	8532	11820	2944
lru	3767	4510	4204	4461	2415
hyperlru-object	3419	4274	4253	4260	2297
simple-lru-cache	2822	4107	4007	4184	2268
js-lru	2754	5812	4508	5021	1753
secondary-cache	2536	4593	4596	8365	1602
lru-cache	1920	2530	2643	2690	1331
hyperlru-map	1750	1994	2381	1980	1292
modern-lru	2020	2881	2530	2994	1082
mkc	1376	1747	994	1892	877

and node v12:

name	set	get1	update	get2	evict
mnemonist-object	9906	49505	37951	55402	7843
hashlru	14225	14925	16935	15432	6768
simple-lru-cache	5922	33113	31153	38314	6714
lru-fast	5061	30488	29762	40486	5610
tiny-lru	4692	36298	36166	37665	5345
quick-lru	5288	3579	4445	3376	5230
hyperlru-object	3958	13072	12516	11338	3199
mnemonist-map	3871	7307	6305	7361	2736
lru	2757	4107	3867	4570	2502
secondary-cache	2612	7770	4906	9510	2098
js-lru	2679	7192	5075	5833	1587
hyperlru-map	1535	4161	3589	4265	1422
lru-cache	1664	4350	3311	4309	1365
mkc	1498	2076	1275	2102	1010
modern-lru	1730	2657	2061	2634	1007

Any idea what engine optimization could have caused this? (Ran code is the same, I checked).