▁( single ▁core ) ▁systems . ▁In ▁these ▁systems , ▁MS Is ▁are ▁handled ▁by ▁writing ▁the ▁interrupt ▁vector ▁directly ▁into ▁the ▁L API C ▁of ▁the ▁processor / core ▁that ▁needs ▁to ▁service ▁the ▁interrupt . ▁The ▁Intel ▁L API C s ▁of ▁ 2 0 0 9 ▁supported ▁up ▁to ▁ 2 2 4 ▁M SI - based ▁interrupt s . ▁According ▁to ▁a ▁ 2 0 0 9 ▁Intel ▁benchmark ▁using ▁Linux , ▁using ▁M SI ▁reduced ▁the ▁laten cy ▁of ▁interrupt s ▁by ▁a ▁factor ▁of ▁almost ▁three ▁when ▁compared ▁to ▁I / O ▁API C ▁delivery . ▁ ▁Oper ating ▁system ▁support ▁ ▁In ▁the ▁Microsoft ▁family ▁of ▁operating ▁systems , ▁Windows ▁V ista ▁and ▁later ▁versions ▁have ▁support ▁for ▁both ▁M SI ▁and ▁M SI - X . ▁Support ▁was ▁added ▁in ▁the ▁Long horn ▁development ▁cycle ▁around ▁ 2 0 0 4 . ▁M SI ▁is ▁not ▁supported ▁in ▁earlier ▁versions ▁like ▁Windows ▁XP ▁or ▁Windows ▁Server ▁ 2 0 0 3 . ▁ ▁Sol aris ▁Express ▁ ▁release ▁ 6 / 0 5 ▁added ▁support ▁for ▁M SI ▁an ▁M SI - X ▁as ▁part ▁of ▁their ▁new ▁device ▁driver ▁interface ▁( D DI ) ▁interrupt ▁framework . ▁ ▁Free B SD ▁ 6 . 3 ▁and ▁ 7 . 0 ▁added ▁support ▁for ▁M SI ▁and ▁M SI - X . ▁ ▁Open B SD ▁ 5 . 0 ▁added ▁support ▁for ▁M SI . ▁ 6 . 0 ▁added ▁support ▁for ▁M SI