Recorded PVE 8 and PVE 9 guest rrddata responses (fixtures under
pkg/proxmox/testdata/rrd/) prove guest RRD never carries the cache-aware
memused/memavailable columns — they exist only in node RRD — so every
consumer branch reading them was dead code that #1634's listing fallback
(7d7d2b6a3) had already routed around.
Drop the two fields from GuestRRDPoint (now time/maxmem only, matching
the recordings), delete the dead VM RRD memory fallback and its
getVMRRDMetrics/getVMRRDMemory helpers plus the vmRRDMemCache they fed,
remove the pointless per-poll guest RRD fetch from the LXC memory path,
and retire the guest RRD lookups from PVEClientInterface. VMMemoryRaw
loses its never-populated RRD diagnostic fields, and guest reliability
scoring no longer treats the node-only rrd-* sources as trusted guest
evidence. The knownDeadGuestRRDFields allowlist in the fixture
alignment test is gone; a new reflection guard in
code_standards_test.go keeps GuestRRDPoint pinned to recorded columns,
and cleanupRRDCache pruning of the guest-agent meminfo cache gains
direct coverage.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
When the Proxmox API's meminfo/status payload omits Available, Buffers,
and Cached (common for QEMU guest-agent and node status responses), the
code derived 'available' from Free alone — producing used = Total-Free
which counts reclaimable page cache as used memory (e.g. 94% instead of
the correct 76%).
Guest path (deriveGuestMemInfoAvailable): return 0 when cache metrics
are completely missing and only Free is available, so resolveGuestStatusMemory
tries better sources: guest-agent /proc/meminfo file-read (returns
MemAvailable), RRD memavailable, or the linked host agent.
Node path (resolveNodeMemory): always try RRD memavailable when cache
metrics are missing, not only when effectiveAvailable == 0 — previously
a non-zero Free value blocked the RRD fallback.
Refs #1501
Prefer QEMU guest-agent MemAvailable when Proxmox reports saturated VM memory without guest free fields.
Add regression coverage for the issue #1319 Windows fsinfo volume payload so usable C/E/F volumes remain counted while System Reserved partitions are skipped.
Refs #1319
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