Reduce first impression latency

Initializing an app with long waterfall mediation chains and multiple third party adapters can increase ad request latency for critical impressions that show first in the user's session. This increased first impression latency can prevent the ad from showing as the ad request has not yet returned a response.

This guide covers the following to reduce first impression latency in your app sessions:

• Set an initialization timeout
• Remove waterfall ad sources from your first request
• Improve performance on less time-sensitive impressions

Before you begin

Before you continue, set up GMA Next-Gen SDK.

Set an initialization timeout

To avoid missing an impression opportunity, set an initialization timeout. This approach prevents your app from exceeding the time limit you defined. You can proceed with the ad request after the time limit you set, or after initialization completes.

To set a timeout and have precise control over the exact adapters you initialize, see Use configurable adapter initialization.

The following example creates an adapter initialization configuration and sets an initialization timeout of five seconds:

val adapterConfig =
  AdapterInitializationConfig.Builder()
    .setAllowedAdFormats(setOf(AdFormat.APP_OPEN_AD))
    .setInitializationTimeoutMs(5000)
    .build()
ConfigurableInitSnippets.kt

AdapterInitializationConfig adapterConfig =
    new AdapterInitializationConfig.Builder()
        .setAllowedAdFormats(Set.of(AdFormat.APP_OPEN_AD))
        .setInitializationTimeoutMs(5000)
        .build();
ConfigurableInitSnippets.java

For more information, see Use configurable adapter initialization.

Remove waterfall ad sources on your first request

To deliver ads without any additional latency from waterfall ad sources, implement key-value segmentation to remove waterfall ad sources on your first ad request. Complete the following steps:

1. Create a mediation group and add bidding ad sources.
2. Add key-value segmentation to your new bidding-only mediation group using key latency and value low.
3. Prioritize your new bidding-only mediation group above your primary mediation group in the UI. To adjust the order, change mediation group priority.

4. In your first ad request, include the custom targeting key-value pair:

   Kotlin

   val request = AdRequest.Builder("AD_UNIT_ID")
       .putCustomTargeting("latency", "low")
       .build()
   

   Java

   AdRequest request = new AdRequest.Builder("AD_UNIT_ID")
       .putCustomTargeting("latency", "low")
       .build();
   

5. Test the key-value segmentation setup to verify you are correctly targeting the new bidding-only mediation group.

Improve performance on less time-sensitive impressions

To improve performance on less time-sensitive impressions, such as ads that don't need to show right at app launch, use ad preloading with an ad request that does not target the bidding-only mediation group.