On Tue, 31 Oct 2023 at 15:41, 赵晨 <winters.zc@xxxxxxxxxxxx> wrote: > > After the fuse daemon crashes, the fuse mount point becomes inaccessible. > In some production environments, a watchdog daemon is used to preserve > the FUSE connection's file descriptor (fd). When the FUSE daemon crashes, > a new FUSE daemon is restarted and takes over the fd from the watchdog > daemon, allowing it to continue providing services. > > However, if any inflight requests are lost during the crash, the user > process becomes stuck as it does not receive any replies. > > To resolve this issue, this patchset introduces two sysfs APIs that enable > flushing or resending these pending requests for recovery. The flush > operation ends the pending request and returns an error to the > application, allowing the stuck user process to recover. While returning > an error may not be suitable for all scenarios, the resend API can be used > to resend the these pending requests. > > When using the resend API, FUSE daemon needs to ensure proper recording > and avoidance of processing duplicate non-idempotent requests to prevent > potential consistency issues. Do we need both the resend and the flush APIs? I think the flush functionality can easily be implemented with the resend API, no? Thanks, Miklos
