With AS SSD Benchmark you can determine your SSD drive's performance by conducting several specific tests.
Test the sequential or random read/write performance without using the cache. AS SSD Benchmark reads/writes a 1 GByte file as well as randomly chosen 4K blocks. Additionally, it performs the tests using 1 or 64 threads and it determines the SSD's access time.
Two extra benchmark tests examine the drive's behaviour when (1) copying a few big files, a lot of small files and a mixture of file sizes by using cached copy functions of your OS as well as (2) reading/writing data depending on the data's compressibility.