Bisected: The Unfortunate Reason Linux 4.20 Is Running Slower (phoronix.com) 18 points by rsendv 7y ago ↗ HN
[–] craftyguy 7y ago ↗ tl;dr: The cause is the Single Thread Indirect Branch Predictors (STIBP) for cross-hyperthread Spectre mitigation on Intel processors.I'm not sure why Michael thinks this is a surprise, performance regressions were practically on the box with these mitigations. [–] liamkinne 7y ago ↗ I don't get the general shock that people have over these mitigations slowing performance.Yeah we're throwing out the cash more often, of course it's going to be slower. [–] craftyguy 7y ago ↗ It gets websites more clicks. [–] FartyMcFarter 7y ago ↗ A 30% performance drop is pretty shocking.
[–] liamkinne 7y ago ↗ I don't get the general shock that people have over these mitigations slowing performance.Yeah we're throwing out the cash more often, of course it's going to be slower. [–] craftyguy 7y ago ↗ It gets websites more clicks. [–] FartyMcFarter 7y ago ↗ A 30% performance drop is pretty shocking.
5 comments
[ 3.6 ms ] story [ 20.6 ms ] threadI'm not sure why Michael thinks this is a surprise, performance regressions were practically on the box with these mitigations.
Yeah we're throwing out the cash more often, of course it's going to be slower.