Scripting Regular expression considered too many characters – How to solve this Elasticsearch exception

Opster Team

August-23, Version: 7.1-7.15

Briefly, this error occurs when a regular expression (regex) used in a script is too complex or large, causing Elasticsearch to reject it due to potential performance issues. To resolve this, you can simplify the regex or break it down into smaller parts. Alternatively, consider using a different approach to achieve the same result, such as using Elasticsearch’s built-in text analysis features or creating a custom analyzer.

This guide will help you check for common problems that cause the log ” [scripting] Regular expression considered too many characters; ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: .

Log Context

Log “[scripting] Regular expression considered too many characters;” class name is We extracted the following from Elasticsearch source code for those seeking an in-depth context :

 public char charAt(int index) {
 if (counter.hitLimit()) {
 throw new CircuitBreakingException("[scripting] Regular expression considered too many characters; " + details() +
 "; this limit can be changed by changed by the [" + CompilerSettings.REGEX_LIMIT_FACTOR.getKey() + "] setting";
 return wrapped.charAt(index);