$$ head testfile_22mb.txtv^zEh6p7qQn($_%8UMl@\)z3rZy#b"JJtf;n"S]#}^y^i3X(5U$7xv7OWU"e/):\f>kZGjL5OnMQ5)a9d?T@MSU9.8{Dye\CSJZbB#El_GSM*AY=pbiXX1Wf%Jj>:ZrueyL(/Y^=5TyG(8d4hHl"T;.c4`(v7[L#4Jjf!-`i80/5cC[T'}D\Q\4Pv<.Xq}&%9@\g%P"i9|8lOS$Ge`sOV9vytDvj'2JoWif2;tBI1O"0isnG0UCb_NUG:n{|`{Wi9fN.^iYE?}q9ol#b0MUDctWnV>U_JFWhlzug!tglJPq,t!nzw'l_MEYZd:YF|jc:-z`3&8"E^thk!IWE'd.g_-Cf'x]dqhE9S#2`L0bEPiyC3Bjf[^8rsTjeB>v9Q357i8FHk4>TyTKzB<*=!nJ7\DyXe4;[?:u9yN"aP9Q3AE}b>%@q%}d0?\(uh29NTICsYE>izM*-J;vjieLh}`fx<XTgHY'RAH\5aD="H9$eHy7GCcZrM4kufnvh&XQNl7wtS_Yf)AJtpw\m\\'XU`pJn3r+L(,+v3Y(u6OC%cX#dQH<}K:pb{PyWm:Kmf#2Uq1L{ox=:[w(FnX+lDm+ge&qy++$c)&RS+>;:&P!_^"Ubci[>uKC!HG^iiWY.C^}U&q<l4Nx%\[Mkm:3`m).+70lmi|IQY|J6-jjyEh\,`\C?X%4z2kO/4UqgElA\^im%%9WLQw[O1,>;8`+-@j"\*ND/-a`c*P$LiU%V82Ocl;x)iK@&tJmKMNxMoH>D@7)jX.$q&Io2SODUy;ERj=Stbk0,Yx^^Qf{9$[|?13=9Z<=x?fk61%E`t9dClB]}ZGc#xinEZ`U1U@vq8')fSQ&u{G;H+wg3@=F,FQ'p1d=(0MyBo/rX\ej+YGVDM(|S4/,Plw`zJo9#Qc`t}Rf1NoC4;,@8*Cp_P=!%p86>i34{}2u?FGCkE/)R9!BxQSJ]?m4OMqj|@Xxk64ytR^F`{.kmT5I;PLAwOBxRu@xD#Q9:06_<YhUy'Kr6}VG}-2`E`:Ge^BnBT*%'!tLV`wX]qo2<1Q0cfv+=;UrWSj,2G-1j7z97Sy9aj93|M2X{|}mCNs[MZ^"Qs%Wt]CO/j?CyTlo]&>\6gxR^=S|c9.6G}y3m;32[j3e.0f\(pC9n9FN`LO;N)T$AXY"pLblBaA8ztKWIXGK#|6N?REvu%F53;G$3n:JJI7kx>Q9<h29}^CnvmO<!?=*9LI?|:L^Fd{=U8^f^`)ej@|D0Ifp`G(R5=Hx6z!T/'>d3pf^vD1zG@BN29d'i&`t$$
And I tested the existence of pattern "XYZ" with grep, sed, awk and Perl.
Time taken, in descending order is -
Code:
$
$
$ time perl -ne 'print if /XYZ/' testfile_22mb.txt 1>/dev/null
real 0m0.982s
user 0m0.015s
sys 0m0.015s
$
$ time sed -n '/XYZ/p' testfile_22mb.txt 1>/dev/null
real 0m0.771s
user 0m0.624s
sys 0m0.062s
$
$ time awk '/XYZ/' testfile_22mb.txt 1>/dev/null
real 0m0.300s
user 0m0.186s
sys 0m0.031s
$
$ time grep "XYZ" testfile_22mb.txt 1>/dev/null
real 0m0.152s
user 0m0.077s
sys 0m0.015s
$
$
A few microseconds less than if I had actually printed the results; each case matches and prints 31 lines.
So, not much difference if done once. But it will add up if you are doing this a gazillion times inside a loop.
tyler_durden
Last edited by durden_tyler; 09-13-2010 at 04:45 PM..
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