Maanta waxaan rabnaa inaan ka hadalno qaar ka mid ah cusbooneysiinta ugu dambeysay ee nidaamka Sherlock [tani waa koox wax qabad sare leh oo ka tirsan Jaamacadda Stanford - qiyaastii. trans.], taas oo si weyn u dedejisa liiska faylalka hagayaasha leh tiro badan oo la galiyay.
Si ka duwan maqaallada caadiga ah, tani waa warbixin dheeraad ah oo ku saabsan sida aan si joogto ah uga shaqeyno Sherlock si aan ugu sii wadno sida ugu fiican isticmaalayaashayada. Waxaan rajeyneynaa inaan daabacno maqaalo badan oo sidan oo kale ah mustaqbalka.
Liistada faylal badan waxay qaadataa waqti
Dhammaantood waxay ku bilaabeen su'aal taageero farsamo oo ka timid isticmaale. Waxa uu ka warbixiyey dhibaatada uu ku hayo xukunka ls waxay ku qaadataa dhowr daqiiqo buug hage ah oo ay ku jiraan in ka badan 15 oo la soo galiyay $SCRATCH [tusaha faylasha ku meel gaadhka ah - qiyaastii. waddo].
Kumanaan faylal ah oo ku jira hal buug ayaa inta badan culays ku ah nidaamka faylka oo runtii laguma talinayo. Isticmaaluhu wuu ogaa tan oo wuxuu qirtay inaysan wanaagsanayn, laakiin wuxuu xusay in liisku 1000 jeer ka dhaqso badan yahay laptopkiisa Sherlock. Dabcan, tani way na dhaawacday. Markaa si qoto dheer ayaan u eegnay.
Sababtoo ah ls waxay u egtahay mid fiican
Waxaan eegnay waxa ay dhab ahaantii qabato ls markaad taxayso hagaha, iyo sababta hawshu u qaadanayso waqti dheer. Inta badan qaybinta casriga ah ls Sida caadiga ah waxay u socotaa sidii ls --color=auto, sababtoo ah qof kastaa wuu jecel yahay midabada.
Laakiin midabada quruxda badani waxay ku yimaadaan qiimo: fayl kasta ls waa in la helaa macluumaadka ku saabsan nooca faylka, ogolaanshihiisa, calamada, sifooyinka la dheereeyey iyo wixii la mid ah si loo doorto midabka ku habboon.
Mid ka mid ah xalalka fudud ee dhibaatada ayaa ah in la joojiyo midabka guud ahaan, laakiin qiyaas carada isticmaalayaasha. Xaaladna ma aha inaad iska saarto wax soo saarka midabka, ma nihin xayawaan.
Markaa si qoto dheer ayaan u eegnay. ls gelinta midabada iyadoo loo marayo doorsoomka deegaanka LS_COLORS, kaas oo la dhigay dircolors(1) ku salaysan faylka qaabeynta dir_colors(5). Haa, (iyo haddii aadan aqoonin faylalka (samayn), ka dibna dir_midab , Inkastoo wax walba).
Aan si hoose u eegno
Si loo go'aamiyo nidaamka midabka keena hoos u dhaca, waxaanu abuurnay jawi tijaabo ah:
$ mkdir $SCRATCH/dont
$ touch $SCRATCH/dont/{1..10000} # don't try this at home!
$ time ls --color=always $SCRATCH/dont | wc -l
10000
real 0m12.758s
user 0m0.104s
sys 0m0.699s12,7 ilbiriqsi 10 oo fayl ah, ma fiicna.
Dhanka kale, waxaan u baahanahay calan
--color=always: inkastoo uu u soo jeestayls --color=auto, laakiinlswuxuu ogaadaa marka aan lagu xidhin terminaalka (tusaale tuubooyin ama jihaynta wax soo saarka) oo wuxuu baabi'iyaa midabaynta haddii lagu rakiboauto. Nin xariif ah.
Haddaba maxaa waqti dheer qaadanaya? Waanu eegnay strace:
$ strace -c ls --color=always $SCRATCH/dont | wc -l
10000
% time seconds usecs/call calls errors syscall
------ ----------- ----------- --------- --------- ----------------
44.21 0.186617 19 10000 lstat
42.60 0.179807 18 10000 10000 getxattr
12.19 0.051438 5 10000 capget
0.71 0.003002 38 80 getdents
0.07 0.000305 10 30 mmap
0.05 0.000217 12 18 mprotect
0.03 0.000135 14 10 read
0.03 0.000123 11 11 open
0.02 0.000082 6 14 close
[...]
Wow: 10 wicitaan lstat(), 10 wicitaan getxattr() (kuwaas oo dhamaantood guul daraystay sababtoo ah deegaankeenu ma laha sifooyinka ls ay raadinayso), 10 wicitaan capget().
Hubaal tani waa la hagaajin karaa
Sifada kartida? Maya
Talo raac , waxaanu isku daynay inaanu joojino hubinta sifada :
$ eval $(dircolors -b | sed s/ca=[^:]*:/ca=:/)
$ time strace -c ls --color=always $SCRATCH/dont | wc -l
10000
% time seconds usecs/call calls errors syscall
------ ----------- ----------- --------- --------- ----------------
98.95 0.423443 42 10000 lstat
0.78 0.003353 42 80 getdents
0.04 0.000188 10 18 mprotect
0.04 0.000181 6 30 mmap
0.02 0.000085 9 10 read
0.02 0.000084 28 3 mremap
0.02 0.000077 7 11 open
0.02 0.000066 5 14 close
[...]
------ ----------- ----------- --------- --------- ----------------
100.00 0.427920 10221 6 total
real 0m8.160s
user 0m0.115s
sys 0m0.961s
Wow, ilaa 8 ilbiriqsi oo dardargelin ah! Waxaan ka takhalusnay dhammaan wicitaannadaas qaaliga ah getxattr(), iyo caqabadaha capget() la waayay sidoo kale, weyn.
Laakiin waxaa weli jira baaqyadan dhibsada lstat(), Inkastooβ¦
Immisa ubax ayaad u baahan tahay?
Sidaa darteed, waxaan si qoto dheer u eegnay LS_COLORS.
Marka hore waxaanu si fudud u curyaaminay doorsoomahan:
$ echo $LS_COLORS rs=0:di=01;34:ln=01;36:mh=00:pi=40;33:so=01;35:do=01;35:bd=40;33;01:cd=40;33;01:or=40;31;01:su=37;41:sg=30;43:ca=:tw=30;42:ow=34;42:st=37;44:ex=01;32:*.tar=01;31:*.tgz=01;31:*.arc=01;31:*.arj=01;31:*.taz=01;31:*.lha=01;31:*.lz4=01;31:*.lzh=01;31:*.lzma=01;31:*.tlz=01;31:*.txz=01;31:*.tzo=01;31:*.t7z=01;31:*.zip=01;31:*.z=01;31:*.Z=01;31:*.dz=01;31:*.gz=01;31:*.lrz=01;31:*.lz=01;31:*.lzo=01;31:*.xz=01;31:*.bz2=01;31:*.bz=01;31:*.tbz=01;31:*.tbz2=01;31:*.tz=01;31:*.deb=01;31:*.rpm=01;31:*.jar=01;31:*.war=01;31:*.ear=01;31:*.sar=01;31:*.rar=01;31:*.alz=01;31:*.ace=01;31:*.zoo=01;31:*.cpio=01;31:*.7z=01;31:*.rz=01;31:*.cab=01;31:*.jpg=01;35:*.jpeg=01;35:*.gif=01;35:*.bmp=01;35:*.pbm=01;35:*.pgm=01;35:*.ppm=01;35:*.tga=01;35:*.xbm=01;35:*.xpm=01;35:*.tif=01;35:*.tiff=01;35:*.png=01;35:*.svg=01;35:*.svgz=01;35:*.mng=01;35:*.pcx=01;35:*.mov=01;35:*.mpg=01;35:*.mpeg=01;35:*.m2v=01;35:*.mkv=01;35:*.webm=01;35:*.ogm=01;35:*.mp4=01;35:*.m4v=01;35:*.mp4v=01;35:*.vob=01;35:*.qt=01;35:*.nuv=01;35:*.wmv=01;35:*.asf=01;35:*.rm=01;35:*.rmvb=01;35:*.flc=01;35:*.avi=01;35:*.fli=01;35:*.flv=01;35:*.gl=01;35:*.dl=01;35:*.xcf=01;35:*.xwd=01;35:*.yuv=01;35:*.cgm=01;35:*.emf=01;35:*.axv=01;35:*.anx=01;35:*.ogv=01;35:*.ogx=01;35:*.aac=00;36:*.au=00;36:*.flac=00;36:*.mid=00;36:*.midi=00;36:*.mka=00;36:*.mp3=00;36:*.mpc=00;36:*.ogg=00;36:*.ra=00;36:*.wav=00;36:*.axa=00;36:*.oga=00;36:*.spx=00;36:*.xspf=00;36: $ unset LS_COLORS $ echo $LS_COLORS $ time ls --color=always $SCRATCH/dont | wc -l 10000 real 0m13.037s user 0m0.077s sys 0m1.092s
Waa maxay!?! Weli 13 ilbiriqsi?
Waxaa soo baxday in marka doorsoom deegaanka LS_COLORS Mid kaliya oo ka mid ah curiyeheeda ayaan la qeexin ama maqan <type>=color:, waxay u isticmaashaa kaydka ku dhex jira si caadi ah oo wali waxay isticmaashaa midabyo. Markaa haddii aad rabto inaad curyaamiso midabaynta nooc fayl gaar ah, waxaad u baahan tahay inaad ku tirtirto <type>=: ama <type> 00 faylka ku jira DIR_COLORS.
Tijaabooyin badan iyo khaladaad badan ka dib, waxaan ku soo koobnay raadintayadii sidan:
EXEC 00
SETUID 00
SETGID 00
CAPABILITY 00oo u qoran sida
LS_COLORS='ex=00:su=00:sg=00:ca=00:'
Tani waxay ka dhigan tahay: ha midabayn faylasha sifo. , laakiin xoogaa xoogaa ah , midna ma aha .
Waanu dedejinaynaa ls
Oo haddii aadan samayn mid ka mid ah jeegaga, markaas wac lstat() baaba'a, oo hadda waa arrin gebi ahaanba ka duwan:
$ export LS_COLORS='ex=00:su=00:sg=00:ca=00:'
$ time strace -c ls --color=always $SCRATCH/dont | wc -l
10000
% time seconds usecs/call calls errors syscall
------ ----------- ----------- --------- --------- ----------------
63.02 0.002865 36 80 getdents
8.10 0.000368 12 30 mmap
5.72 0.000260 14 18 mprotect
3.72 0.000169 15 11 open
2.79 0.000127 13 10 read
[...]
------ ----------- ----------- --------- --------- ----------------
100.00 0.004546 221 6 total
real 0m0.337s
user 0m0.032s
sys 0m0.029s0,3 ilbiriqsi ee liiska 10 oo faylal, rikoor.
Dejinta Sherlock
Laga bilaabo 13 ilbiriqsi oo leh jaangooyo default ah ilaa 0,3 sekan oo leh hagaajin yar LS_COLORS macneheedu waa dardar 40 laabma maqnaanshaha awgeed setuid / setgid iyo faylal la fulin karo oo midab leh. Ma aha khasaare sidaas u weyn.
Dabcan, kan hadda waxaa lagu habeeyay Sherlock isticmaale kasta.
Laakiin haddii aad rabto inaad soo celiso midabaynta, waxaad si fudud ugu noqon kartaa goobaha caadiga ah:
$ unset LS_COLORS
Laakin ka dib hagaha hagayaasha leh faylal badan, iska hubi inaad kariso kafeega inta uu socdo ls.
Source: www.habr.com