smp: put a cache line between smp statistics structures
smp: put a cache line between smp statistics structures

CPU may automatically prefetch next cache line, so if statistics that
are collected on different cpus resided on adjacent cache lines CPU may
erroneously prefetch cache line that is guarantied to be accessed by
another CPU. Fix it by putting a cache line between two structures.

phonkee/scylla,rentongzhang/scylla,norcimo5/seastar,ducthangho/imdb,justintung/scylla,slivne/seastar,duarten/scylla,raphaelsc/seastar,scylladb/scylla,guiquanz/scylla,capturePointer/scylla,phonkee/scylla,stamhe/scylla,raphaelsc/seastar,scylladb/seastar,dwdm/seastar,avikivity/seastar,justintung/scylla,phonkee/scylla,acbellini/seastar,dreamsxin/seastar,shyamalschandra/seastar,scylladb/scylla,bowlofstew/seastar,senseb/scylla,scylladb/seastar,bowlofstew/seastar,avikivity/seastar,ducthangho/imdb,senseb/scylla,linearregression/scylla,wildinto/seastar,joerg84/seastar,victorbriz/scylla,gwicke/scylla,stamhe/seastar,kjniemi/scylla,leejir/seastar,leejir/seastar,mixja/seastar,kangkot/scylla,kjniemi/scylla,stamhe/scylla,senseb/scylla,koolhazz/seastar,anzihenry/seastar,bowlofstew/scylla,scylladb/scylla,respu/scylla,aruanruan/scylla,koolhazz/seastar,wildinto/scylla,norcimo5/seastar,sjperkins/seastar,dwdm/scylla,rentongzhang/scylla,joerg84/seastar,xtao/seastar,sjperkins/seastar,rluta/scylla,printedheart/seastar,tempbottle/scylla,stamhe/seastar,gwicke/scylla,stamhe/scylla,flashbuckets/seastar,printedheart/seastar,avikivity/scylla,shaunstanislaus/scylla,jonathanleang/seastar,kjniemi/seastar,ducthangho/imdb,tempbottle/scylla,raphaelsc/scylla,jonathanleang/seastar,duarten/scylla,guiquanz/scylla,bzero/seastar,hongliangzhao/seastar,xtao/seastar,hongliangzhao/seastar,xtao/seastar,flashbuckets/seastar,scylladb/scylla-seastar,kangkot/scylla,linearregression/seastar,bowlofstew/scylla,jonathanleang/seastar,joerg84/seastar,cloudius-systems/seastar,kjniemi/seastar,eklitzke/scylla,glommer/scylla,scylladb/scylla-seastar,anzihenry/seastar,acbellini/seastar,dreamsxin/seastar,mixja/seastar,eklitzke/scylla,scylladb/scylla-seastar,koolhazz/seastar,avikivity/scylla,rentongzhang/scylla,respu/scylla,sjperkins/seastar,printedheart/seastar,aruanruan/scylla,wildinto/scylla,kjniemi/scylla,acbellini/scylla,avikivity/seastar,flashbuckets/seastar,linearregression/seastar,acbellini/seastar,duarten/scylla,kangkot/scylla,dreamsxin/seastar,hongliangzhao/seastar,chunshengster/seastar,wildinto/seastar,capturePointer/scylla,tempbottle/seastar,glommer/scylla,dwdm/scylla,respu/scylla,glommer/scylla,aruanruan/scylla,syuu1228/seastar,eklitzke/scylla,asias/scylla,asias/scylla,slivne/seastar,scylladb/seastar,rluta/scylla,bzero/seastar,acbellini/scylla,linearregression/scylla,dwdm/seastar,tempbottle/seastar,bzero/seastar,bowlofstew/seastar,bowlofstew/scylla,dwdm/seastar,wildinto/seastar,shyamalschandra/seastar,syuu1228/seastar,asias/scylla,victorbriz/scylla,raphaelsc/scylla,wildinto/scylla,avikivity/scylla,slivne/seastar,stamhe/seastar,shaunstanislaus/scylla,chunshengster/seastar,syuu1228/seastar,victorbriz/scylla,capturePointer/scylla,chunshengster/seastar,gwicke/scylla,guiquanz/scylla,anzihenry/seastar,shyamalschandra/seastar,mixja/seastar,cloudius-systems/seastar,scylladb/scylla,tempbottle/seastar,shaunstanislaus/scylla,norcimo5/seastar,dwdm/scylla,rluta/scylla,linearregression/scylla,linearregression/seastar,tempbottle/scylla,raphaelsc/scylla,leejir/seastar,cloudius-systems/seastar,raphaelsc/seastar,justintung/scylla,acbellini/scylla,kjniemi/seastar