ZSON is a PostgreSQL extension for transparent JSONB compression. Compression is based on a shared dictionary of strings most frequently used in specific JSONB documents (not only keys, but also values, array elements, etc). In some cases ZSON can save half of your disk space and give you about 10% more TPS. Memory is saved as well. See docs/benchmark.md. Everything depends on your data and workload, though. Don't believe any benchmarks, re-check everything on your data, configuration, hardware, workload and PostgreSQL version.