ImageMagick7 runs much slower than version6

[fmw42]

Correct. That is what I wrote earlier in this topic.

[niyanwen]

the one you talk about limit thread is this below?
convert -limit thread 1 src.png -resize 4000x5000! -format %@ -write info: -trim +repage -bordercolor none -border 5 dest.png

I try this but got errors

[fmw42]

It works fine for me.

Code: Select all

convert -limit thread 1 b07s8dt2vc-large-front_image.png -resize 4500x5400! -format %@ -write info: -trim +repage -bordercolor none -border 5 result.png

3739x5194+452+57

[niyanwen]

Hi,
does that mean HDRI has been disabled?
looks like it is still slow. do I need also disable OpenMP? if it is, do you know how to do it?

[niyanwen@mftp-ygw-i-d-2a-43520b1f]/apollo/env/MerchFTProductionAssetManagerService/bin% ./convert -version
Version: ImageMagick 7.0.8-37 Q16 x86_64 2019-10-08 https://imagemagick.org
Copyright: © 1999-2019 ImageMagick Studio LLC
License: https://imagemagick.org/script/license.php
Features: Cipher DPC OpenMP
Delegates (built-in): bzlib fontconfig freetype jng jp2 jpeg lcms png raw tiff webp xml zlib

[fmw42]

-limit thread 1 just disable your 16 processors and forces Imagemagick to use just 1. It has nothing to do with HDRI. To disable HDRI or OpenMP, you have to recompile ImageMagick. I doubt disabling OpenMP will make a difference since -limit thread 1 did not seem to help.

[niyanwen]

oh I haven't try limit 1 yet, now I just tried disable HDR I found in some posts says it will help, I saw another suggestion is try add -quality 21?
https://www.imagemagick.org/discourse-s ... hp?t=27672

[niyanwen]

looks like limit thread helps and speed improve a lot!

[niyanwen]

-limit thread 1 just disable your 16 processors and forces Imagemagick to use just 1. It has nothing to do with HDRI. To disable HDRI or OpenMP, you have to recompile ImageMagick. I doubt disabling OpenMP will make a difference since -limit thread 1 did not seem to help.

just one concern is what do you mean disable 16 processors and force to just use 1?
for if this host has another image magick command running, is it acceptable?

[fmw42]

It only disables the other processors for the command for which -limit is set, not for the server. But that did not help, so no point in doing -limit. However, if your hosting provided disables OpenMP or HDRI, that would affect the whole server and all users. So that is not likely going to happen if you are on a shared server.

[snibgo]

Multi-threading can be disabled per command, but HDRI is a build-level switch.

I use at least two versions of IM: HDRI when I need precision, and non-HDRI when I need speed. This may not be feasible on a shared server.

[niyanwen]

limit thread help, so now I am doing 1. limit 2. disable HDR 3. add quality to improve the speed, thank you guys!

[niyanwen]

IM6 is limit thread 1 by default?

[snibgo]

IM6 is limit thread 1 by default?

No. "convert -list resource" shows the limit:

Code: Select all

Resource limits:
  Width: 214.7MP
  Height: 214.7MP
  List length: 18.446744EP
  Area: 6.4068GP
  Memory: 2.9834GiB
  Map: 5.9668GiB
  Disk: unlimited
  File: 1536
  Thread: 8  <<========
  Throttle: 0
  Time: unlimited

On my computer, the limit is 8.