Question about the slow tag killing / force timeout feature.

[koen_crommentui]

In the publish settings there is the option "Force timeout" to kill slow loading tags. This is the description of the feature in the Tealium interface: "Set this value to time out slow-loading libraries. If a library has not loaded before this time expires, the library will be removed from the load queue, and the remaining tags will continue to load. This is typically needed if libraries are loaded on-premise or from a custom location. The value is in milliseconds." I've got some questions here. Is it on by default, and what is the default timeout? What is the definition of a library, is it a utag.x.js file? What is the definition of loaded (when does the timer start, and when does is end)? Thanks in advance.

[son_hoang]

Hi Koen, Answers regarding the publish settings for 'force timeout': 1. Yes it is on by default, the default value is 3 seconds, or 3000 ms, although the UI example shows 4000. 2. Yes. utag.x.js are the individual tag libraries, e.g. Google Analytics, SiteCatalyst. 3. The timer starts when utag.js is called, not when utag.x.js is called. The timer ends at whatever value you set, or at 3000 ms by default. Please note though that as long as you are doing async loading, we encourage you to increase this time to a higher value. With async loading, a slow tag will not prevent your page from loading (i.e. 'non-blocking'), so there isn't as much reason as there used to be to kill a tag off. This is especially important in development environments where connections tend to be slower, or for mobile users who tend to be on slower and less-consistent connections. Additionally, sometimes a tag isn't loading slowly at all, but may simply be in a queue behind other page assets, such as images, or even Flash elements. So by the time the page gets around to loading a tag, it might not have even started loading but the timeout might've already expired it. There are also other factors to consider, such as simultaneous connections per domain (older browsers only allowed 2, current versions allow up to 8). Basically, sometimes a tag isn't loading not because it's slow, but because it just isn't getting its turn to load yet. Hope this helps!

[rob_van_eijk]

Hi Son, Thank you for your reply. That helps a lot! I have an additional question: Does slow tag killing also incorporate killing of slow tag execution (as opposed to slow tag loading)? As an example: My page includes utag.1.js, which loads within the set time-out period, but takes very long to execute (e.g., because sends a pixel request to an external domain that is either down or very slow). Will slow tag killing also abort execution of the script that is contained "within" utag.1.js? Or will it only kill the loading of utag.x.js files? Thanks!

[son_hoang]

We have two related features, Force Timeout, which I discussed, and Tag Timeout. Force Timeout only works as detailed. Tag Timeout only works with about 3 tags currently, one of which is the Tealium Pixel Container Tag. And it works in that if a pixel request is not returned by the time set, it will cancel the request. However if the request involves an iFrame, which many tags do call, we cannot time those out.

[rob_van_eijk]

Hi Son, Many thanks for your reply. Can you indicate for what other Tags (besides the Pixel Container Tag) the Tag Timeout currently works? Secondly, is the Tag Timeout on the roadmap to be implemented for additional (ideally all) Tags? Thanks in advance! Best, Rob

[son_hoang]

Tealium Pixel Container Tag is primarily the one that does, since you can use it to fire other tags. Note that any tag that uses i-frame's cannot be timed out or killed simply due to the way web pages work. Since the Pixel Container Tag essentially fires any tag you want, this is especially important to note. Clients can request we add it to specific tags (non-iframe ones), but in my opinion I would not recommend it. If your tag is set to wait for DOM ready to load, and is set to load asynchronously, it should not impact the loading of your page. The files would be non-blocking and would have their own set of loading pipelines to our CDNs which would be separate to the ones to your websites. But if it is something you want added to the tags for your site, please contact your account manager about adding this feature.

[Seth · Accepted solution]

As an update, Tealium has deprecated the Force Timeout publish configuration. It does not affect profiles using utag.js version 4.26 or later. Only earlier versions of utag.js will respect this configuration. You can find more information about the legacy publish configurations here: https://community.tealiumiq.com/t5/Tealium-iQ/Publish-Configurations/ta-p/13632#legacy_settings The Tag Timeout option was removed from Tags' advanced settings as well.