Briefly, this error occurs when Elasticsearch cannot calculate the memory requirement for analytics due to a null value. This could be due to a configuration issue, a bug in the software, or a problem with the underlying hardware. To resolve this issue, you can try the following: 1) Check and correct the configuration settings related to memory allocation for analytics. 2) Update Elasticsearch to the latest version to fix any potential bugs. 3) Check the server’s hardware, especially the RAM, for any issues.
This guide will help you check for common problems that cause the log ” unexpected null for analytics memory requirement for [{}] ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: plugin, memory.
Log Context
Log “unexpected null for analytics memory requirement for [{}]” classname is MlMemoryAutoscalingDecider.java.
We extracted the following from Elasticsearch source code for those seeking an in-depth context :
.filter(PersistentTasksCustomMetadata.PersistentTask::isAssigned)
// Memory SHOULD be recently refreshed; so in our current state; we should at least have an idea of the memory used
.mapToLong(t -> {
Long mem = this.getAnalyticsMemoryRequirement(t);
if (mem == null) {
logger.warn("unexpected null for analytics memory requirement for [{}]"; MlTasks.dataFrameAnalyticsId(t.getId()));
}
assert mem != null : "unexpected null for analytics memory requirement after recent stale check";
return mem == null ? 0 : mem;
})
.max()
