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Re: [ID 20010425.012] VMS Perl pipes 2x slower on Perl 5.6.1compared to Perl 5.5.3

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From:
Craig A. Berry
Date:
April 25, 2001 17:29
Subject:
Re: [ID 20010425.012] VMS Perl pipes 2x slower on Perl 5.6.1compared to Perl 5.5.3
Message ID:
5.0.2.1.0.20010425191508.019921c8@mail.mac.com
Richard,

You are probably right that we have paid a performance penalty to get 
functionality that actually works in a greater range of cases.  There are a 
couple of things to check, though.  First, make sure your process is using 
the copy of vmspipe.com that is in the top-level directory of the Perl 
installation.  Perl will create a temporary copy if it doesn't find the 
file, but the overhead in doing so can be painful.  Second, experiment with 
the value of the logical name PERL_MBX_SIZE.  If it's not defined, we 
default, IIRC, to 512.  Try 2048 or even 8192 if you can do so without 
blowing your BYTLM quota.  And no, this is probably not adequately 
documented outside the comments in the code or the vmsperl archives.  You'll 
find Charles Lane's home-grown piping implementation in [.vms]vms.c --
comments or suggestions for improvement welcome.


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