18284, "ronawho", "Stop communicating from read-only memory", "2021-08-24T18:40:19Z"
Currently, things like our string literals are placed on read-only memory and that has caused a number of issues:
- Bug 3338 – ibv_reg_mr failure (EFAULT/Bad address) on read-only data
- Bug 4008 – testreadonly failure with ibv/odp
- Disable on-demand-paging for gasnet-ibv by ronawho · Pull Request #18245 · chapel-lang/chapel · GitHub
We've also been seeing issues when trying to experiment with gasnet-ibv segment everything that we believe are caused by doing GETs from read-only memory.
Some of these issues have been in gasnet, but others are lower in the software stack. We're the only gasnet client that communicates from read-only memory and I'm starting to think we should just stop doing that.