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Top Forums UNIX for Dummies Questions & Answers What is the faster way to grep from huge file? Post 302960653 by mad man on Wednesday 18th of November 2015 06:04:47 AM
Old 11-18-2015
CPU & Memory What is the faster way to grep from huge file?

Hi All,

I am new to this forum and this is my first post.
My requirement is like to optimize the time taken to grep the file with 40000 lines.

There are two files FILEA(40000 lines) FILEB(40000 lines).
The requirement is like this, both the file will be in the format below
Code:
1~refno001~blah~blah

I will take the refno001 as a search key from FILEA and grep the FILEB. The FILEB will be having the updated value of refno001 as follows.
Code:
1~refno001~blah~good

.

So i will use this record from FILEB in my process. The problem here is i am using below code to grep from FILEB.
Code:
hold_rec=grep "$ref_no" /root/dev/FILEB

But this is taking 20 minutes to complete (i.e 40000 x 40000) search for each and every reference no from FILEA to FILEB. This has to be minized as short as possible.

So kindly guide me if there is any way to reduce the process time to less than 5 mins with any other commands.

Note: my UNIX is AIX 6.0

Last edited by Don Cragun; 11-19-2015 at 02:13 AM.. Reason: Add CODE and ICODE tags.
 

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IRSEND(1)								FSF								 IRSEND(1)

NAME
irsend - basic LIRC program to send infra-red commands SYNOPSIS
irsend [options] DIRECTIVE REMOTE CODE [CODE...] DESCRIPTION
Asks the lircd daemon to send one or more CIR (Consumer Infra-Red) commands. This is intended for remote control of electronic devices such as TV boxes, HiFi sets, etc. DIRECTIVE can be: SEND_ONCE - send CODE [CODE ...] once SEND_START - start repeating CODE SEND_STOP - stop repeating CODE LIST - list configured remote items SET_TRANSMITTERS - set transmitters NUM [NUM ...] SIMULATE - simulate IR event REMOTE is the name of a remote, as described in the lircd configuration file. CODE is the name of a remote control key of REMOTE, as it appears in the lircd configuration file. NUM is the transmitter number of the hardware device. For the LIST DIRECTIVE, REMOTE and/or CODE can be empty: LIST "" "" - list all configured remote names LIST REMOTE "" - list all codes of REMOTE LIST REMOTE CODE - list only CODE of REMOTE The SIMULATE command only works if it has been explicitly enabled in lircd. -h --help display usage summary -v --version display version -d --device use given lircd socket [/var/run/lirc/lircd] -a --address=host[:port] connect to lircd at this address -# --count=n send command n times EXAMPLES
irsend LIST DenonTuner "" irsend SEND_ONCE DenonTuner PROG-SCAN irsend SEND_ONCE OnkyoAmpli VOL-UP VOL-UP VOL-UP VOL-UP irsend SEND_START OnkyoAmpli VOL-DOWN ; sleep 3 irsend SEND_STOP OnkyoAmpli VOL-DOWN irsend SET_TRANSMITTERS 1 irsend SET_TRANSMITTERS 1 3 4 irsend SIMULATE "0000000000000476 00 OK TECHNISAT_ST3004S" FILES
/etc/lirc/lircd.conf Default lircd configuration file. It should contain all the remotes, their infra-red codes and the corresponding timing and wave- form details. DIAGNOSTICS
If lircd is not running (or /var/run/lirc/lircd lacks write permissions) irsend aborts with the following diagnostics: "irsend: could not connect to socket" "irsend: Connection refused" (or "Permission denied"). SEE ALSO
The documentation for lirc is maintained as html pages. They are located under html/ in the documentation directory. lircd(8), mode2(1), smode2(1), xmode2(1), irrecord(1), irw(1), http://www.lirc.org. irsend 0.8.7pre1 May 2010 IRSEND(1)
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