In theory, your comments make perfect sense and your advice is great. I've actually set up a full test environment for these and tried every variation of blocking() including commenting it out as you suggest. I've also tried replacing can_read() with IO::Select::select().

In every single case, the IO::Handle object returns 1 for blocking(), but can_read returns immediately, regardless of timeout value. I am almost 100% certain the parent is not sending any more data than the message that needs to be thawed. No matter what, CPU spikes to 100% in the child until it dies. The only conditions that mitigate this are when I reduce the timeout on can_read() or select and even then CPU is between 60-80% for each child. Improved, but still a resource drain.

I'm very perplexed as to why can_read() and select will not block in this application.

In reply to Re^4: Performance and CPU load: sysread, IO::Select and/or Storable::thaw by DBX
in thread Performance and CPU load: sysread, IO::Select and/or Storable::thaw by DBX

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


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.