A hard-mounted network filesystem with an unreachable server blocks
statfs in an uninterruptible kernel wait. The collector issued that
syscall inline for every mount, so one dead NFS mount silently froze
the whole reporting cycle and stretched agent shutdown into the kernel
retry window, and it paid that price for mounts the fstype filter was
going to discard anyway.
Decide type- and mountpoint-based skips before the usage syscall, so
network filesystems are never probed unless explicitly included, and
bound every remaining usage call with a timeout that leaves at most one
in-flight probe per mountpoint. A mount whose call never returned is
skipped on later cycles and re-included when the stalled call answers.
Refs discussion #1747
Contract-Neutral: Discussion #1747: behavioral bugfix in host disk collection; no payload or API shape change, filtered mounts were never reported
rcourtman
af6d482515