On Mon, 18 Apr 2022 17:37:10 -0400 Gabriel Krisman Bertazi <krisman@xxxxxxxxxxxxx> wrote: > When provisioning containerized applications, multiple very small tmpfs "files"? > are used, for which one cannot always predict the proper file system > size ahead of time. We want to be able to reliably monitor filesystems > for ENOSPC errors, without depending on the application being executed > reporting the ENOSPC after a failure. Well that sucks. We need a kernel-side workaround for applications that fail to check and report storage errors? We could do this for every syscall in the kernel. What's special about tmpfs in this regard? Please provide additional justification and usage examples for such an extraordinary thing. > It is also not enough to watch > statfs since that information might be ephemeral (say the application > recovers by deleting data, the issue can get lost). We could fix the apps? Heck, you could patch libc's write() to the same effect. > For this use case, > it is also interesting to differentiate IO errors caused by lack of > virtual memory from lack of FS space. More details, please. Why interesting? What actions can the system operator take based upon this information? Whatever that action is, I see no user-facing documentation which guides the user info how to take advantage of this?