Update README.md

Author: renanccastro

README.md

@@ -24,7 +24,7 @@ Run your eslint task like: `METEOR_ESLINT_PLUGIN_DEBUG=1 eslint .`
 
 ## Options
 
-- Env var `METEOR_ESLINT_PLUGIN_EXPIRES_CACHE_IN_SECONDS`: default is `5`. You can customize the cache expiration time in seconds.
+- Env var `METEOR_ESLINT_PLUGIN_EXPIRES_CACHE_IN_SECONDS`: default is `5`. You can customize the cache expiration time in seconds. - **This is especially important if you have a big project with several files and it takes a lot of time to analyze. If this value is too low, the cache will expire while the analysis is running, and the lint won´t work.**
 - Env var `METEOR_ESLINT_PLUGIN_DEBUG`: default is disabled. You can pass this to enable debug mode and see more logs.
 - Env var `METEOR_ESLINT_PLUGIN_IGNORE_CACHE`: default is false. You can pass this to ignore the cache.
 - Env var `METEOR_ESLINT_PLUGIN_FILES`: use this if you want to lint a specific file.