I have a project running Java in an app engine which uses com.google.cloud.logging.logback.LoggingAppender to output log like as below.

https://cloud.google.com/logging/docs/setup/java

I found that the latency of log.error output is around 100ms. This means, if the app output error logs too many then app-engine would scale up.

Our app connect to some external services. When those services sometimes respond error, the app output error logs.

Does anyone know how to cope with it?

I expected that flushLevel=OFF would resolve this issue, but OFF=ALL by below method. https://github.com/googleapis/java-logging-logback/blob/0.116.0/google-cloud-contrib/google-cloud-logging-logback/src/main/java/com/google/cloud/logging/logback/LoggingAppender.java#L336-L355

Sorry for my multi post.

https://stackoverflow.com/questions/62786760/q-gae-stackdriver-java-logback-error-logging-too-slow

I contacted Google Support Case and they told me to create an issue about this case.