Beefy Boxes and Bandwidth Generously Provided by pair Networks
Don't ask to ask, just ask
 
PerlMonks  

comment on

( [id://3333]=superdoc: print w/replies, xml ) Need Help??
Hi, BrowserUK's reply looks quite good.

I just would like to chip in that if you are willing to chunk your data file in 100MB bites, based on my timing of unix sort on a 100MB file of 9 digit numbers it would cost you 100 hours to get sort all the data first. If you can at the same time ensure fixed length columns it will help.

You really do not want to do any disk I/O since on my machine it takes 7 hours just to read the file once. If you have sorted kill list that is chunked according to the extents of each data chunk you also only have 1/40 of the kill list to worry about (if distribution is even).


In reply to Re: 15 billion row text file and row deletes - Best Practice? by mattr
in thread 15 billion row text file and row deletes - Best Practice? by awohld

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post; it's "PerlMonks-approved HTML":



  • Are you posting in the right place? Check out Where do I post X? to know for sure.
  • Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
    <code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>
  • Snippets of code should be wrapped in <code> tags not <pre> tags. In fact, <pre> tags should generally be avoided. If they must be used, extreme care should be taken to ensure that their contents do not have long lines (<70 chars), in order to prevent horizontal scrolling (and possible janitor intervention).
  • Want more info? How to link or How to display code and escape characters are good places to start.
Log In?
Username:
Password:

What's my password?
Create A New User
Domain Nodelet?
Chatterbox?
and the web crawler heard nothing...

How do I use this?Last hourOther CB clients
Other Users?
Others lurking in the Monastery: (6)
As of 2024-04-18 13:09 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    No recent polls found