I am working on a batch job which imports data from a legacy database, transforms the data in 3NF and inserts the resulting data into another database (target database). The batch job is written with Spring Batch. While I was developing the steps of the job, I wrote unit tests to test the functionality for each step. But now I am finished with development of the steps and want to test the system in a kind of testing environment before rolling the batch job out to production. Therefore, I imported the legacy database locally on a MySQL server and also created a local version of the target database. These MySQL servers are deployed on my Macbook Pro with 256 GB SSD. I already ran the job a few times with little bugfixes but now it came to my mind that SSDs are more sensible to write cycles than a standard HDD. Hence, I checked the process mysqld in my activity manager and noticed that 424.64 GB have been written to my SSD in the last three days.
How much influence (lifetime, write cycles) does this number of written GB will have to my SSD? Would you recommend to deploy the database on a normal HDD instead of using my SSD? Or do you think that I am falsely alarmed?
I would recommend you deploy the database to a normal HDD, because the NAND flash on your SSD do have a max erase threshold. In other words, you are wearing down your SSD. Although SSDs have features to ensure that the NAND flash wear down evenly, you are definitely wearing it down much faster than normal usage.