We have to be careful when manipulating repository look-ups.  The cache lookups should be case-insensitive - but the filesystem lookups are case-sensitive on case-sensitive filesystems.

I think the better fix is to ensure that cache lookups use the proper key, but leave the file system loading as-is.  Try the following and let me know if that yields the same time-saving result.

```java
String repositoryKey = repositoryName.toLowerCase();
if (!repositoryListCache.containsKey(repositoryKey)) {
    RepositoryModel model = loadRepositoryModel(repositoryName);
    ...
}

// cached model
RepositoryModel model = repositoryListCache.get(repositoryKey);
```