1. A method for adaptive similarity search resolution in a data deduplication system using a processor device in a computing environment, comprising: partitioning input data into input data chunks, the input data chunks each being at least 4 Megabytes (MB) in size; calculating input similarity elements for an input chunk; using the input similarity elements to find similar data in a repository of data using a similarity search structure; calculating a resolution level for storing the input similarity elements, the resolution level comprising a number of the input similarity elements in relation to a size of the input chunk; storing the input similarity elements in the calculated resolution level in the similarity search structure; deduplicating the input chunk with the found similar data in the repository of data using the input similarity units in the calculated resolution level; calculating the resolution level for storing the input similarity elements based on calculated sets of similarity element matches and on a calculated deduplication ratio, the deduplication ratio defined as a total size of the input data covered by matches with repository data out of the total size of the input data; and decreasing the resolution level of the stored input similarity elements if an aggregated deduplication ratio is not lower than a predefined threshold and an average size of the calculated sets of similarity element matches is not lower than two and a current resolution level is higher than a lowest resolution level.