WPML performance issue with DebugBackTrace

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Supporter timezone: Europe/Madrid (GMT+01:00)

Tagged: Performance

This topic contains 6 replies, has 3 voices.

Last updated by adrianM-2 2 weeks, 1 day ago.

Assisted by: Nigel.

Author	Posts
February 11, 2024 at 2:42 pm #15290085
richardL-34	We are currently optimizing several wordpress pages with wpml. It looks like, the DebugBackTrace function uses a huge amount of performance. Is uses abaout 25% (0,255s) from about 1s execution time. Is there a option, to disable this check? If we comment it out / disable with a direct return, we save up to 20% of performance on the page. Thank you for your help! With best regards, Richard Liebmann
February 12, 2024 at 12:00 pm #15292965
Nigel WPML Supporter since 02/2016 Timezone: Europe/Madrid (GMT+01:00)	Hi Richard We recently identified a performance issue arising from the use of debug_backtrace in the context of the WPML SEO add-on, and I can see that you are using that. I'm not sure when a fix will make it into production, but this is part of active work on performance and I expect it to appear in a plugin update before long. I will connect this thread to the internal ticket, and I'll let you know when the update it due for release.
February 26, 2024 at 11:42 am #15343881
richardL-34	Hi Nigel, ok, thanks for your help! I'm looking forward to your response!
May 15, 2024 at 9:28 am #15628858
antonyS-6	Hi We are having the same issue. wp-content/plugins/sitepress-multilingual-cms/classes/utilities/class-debug-backtrace.php Nearly taking 2.5s. Is there a way to disable the backtrace? Disabling WPML SEO reduced this to about 1.8s.
January 27, 2026 at 3:47 pm #17768098
adrianM-2	This still seems to be problem...
January 27, 2026 at 6:07 pm #17768656
Nigel WPML Supporter since 02/2016 Timezone: Europe/Madrid (GMT+01:00)	Updating to WPML SEO 2.2.x should make an appreciable difference to how often the debug backtrace function is called; it doesn't eliminate such calls, but calls originating from the WPML SEO plugin should be reduced to a minimum. We haven't managed to substantially reduce such calls from other sources yet. @adrianM-2 if you are experiencing significant performance issues arising from this could I ask you to open a new thread and share details and access to your site so that we could investigate the specifics of your case?
January 28, 2026 at 4:38 pm #17771395
adrianM-2	@Nigel Thank you for getting back. We are already on the latest version. Doing some analysis I've seen a lot of calls to debug_backtrace too... and came here via Google ... But there is no significant difference in disabling Yoast SEO... Generally WPML uses a lot of resources (seeing the same graphs, WPML always on top...) But I think this is more an issues of WP's non-multilingual core architecture than WPML itself... The screenshot is for an admin post list. --- We've used Code Profiler Pro (same as original thread author). Unfortunately this is not perfect and won't or can't give deep insights in the full call hierarchy ... If you can, you maybe should do some profiling with xdebug, at least it looks like there might be some core level improvements possible with WPML.