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This guide will help you check for common problems that cause the log ” Dropping a warning header; as their total size reached the maximum allowed of ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: thread.
Log Context
Log “Dropping a warning header; as their total size reached the maximum allowed of [” classname is ThreadContext.java.
We extracted the following from Elasticsearch source code for those seeking an in-depth context :
assert value != null;
long newWarningHeaderSize = warningHeadersSize;
//check if we can add another warning header - if max size within limits
if (key.equals("Warning") && (maxWarningHeaderSize != -1)) { //if size is NOT unbounded; check its limits
if (warningHeadersSize > maxWarningHeaderSize) { // if max size has already been reached before
logger.warn("Dropping a warning header; as their total size reached the maximum allowed of ["
+ maxWarningHeaderSize + "] bytes set in ["
+ HttpTransportSettings.SETTING_HTTP_MAX_WARNING_HEADER_SIZE.getKey() + "]!");
return this;
}
newWarningHeaderSize += "Warning".getBytes(StandardCharsets.UTF_8).length + value.getBytes(StandardCharsets.UTF_8).length;
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