[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Openexr-devel] OpenEXR from shared libs.

From: Florian Kainz
Subject: Re: [Openexr-devel] OpenEXR from shared libs.
Date: Fri, 02 Mar 2007 18:32:45 -0800
User-agent: Mozilla Thunderbird 1.0 (X11/20041207)

At least on Linux, the #else version of the AutoArray code,
which allocates memory on the stack, is significantly faster
than the #if version, which calls new[] and delete[].  I tried
reading a sequence of piz-compressed frames (1000x750 pixels,
Y, RY and BY channels) using three parallel threads.  The #if
and #else versions of the AutoArray code run at 25fps and 34fps

I wonder if there is a way to construct and destroy AutoArrays
faster on systems that have small per-thread run-time stacks.


Florian Kainz wrote:
I'll do a couple of tests to see whether there's a significant
speed difference between the #if and the #else versions of the
code.  If they are close, I think I'll remove the #else version

darby johnston wrote:
--- Florian Kainz <address@hidden> wrote:

I wonder if the problem has something to do with the
of the stack when threads are enabled.

Nice one; looks like that fixed it.
How about:

#if defined (HAVE_DARWIN) || defined (_WIN32) \
  || defined (_WIN64) || defined(__FreeBSD__)

Or would a test in the configure script be better?

Thanks, Darby

Openexr-devel mailing list

reply via email to

[Prev in Thread] Current Thread [Next in Thread]