2nd gen is the new standard runtimes using gVisor. I had read comments by googlers here before that the first gen standard runtimes required a lot of custom wor

2nd gen is the new standard runtimes using gVisor. I had read comments by googlers here before that the first gen standard runtimes required a lot of custom work on their end to run on the Google infrastructure which was why they were a bit slow supporting new versions of php, java etc, while the new gvisor based runtimes should be easier to roll out updates.