* shell: make every -collection flag parse the same way
The filter vocabulary (comma-separated names, wildcards, regexes,
"_default" for the empty-named collection) already existed in
wildcard.CompileCollectionMatcher, but several commands still did their
own exact-match comparison or sent the raw flag value to servers.
fs.mergeVolumes used a literal string compare, so -collection=_default
silently produced an empty merge plan; it now uses the shared matcher
while keeping "*" as the match-all default. volume.fsck and volume.mark
filter through the matcher too, and volume.vacuum resolves the filter
client-side into per-collection and per-volume requests, since no
Collection value scopes the VacuumVolume RPC to the unnamed collection
alone.
Commands that put one concrete collection name on the wire normalize
"_default" to "" (volume.grow, fs.configure, mq.topic.compact,
collection.delete, ec.rebuild, ec.balance), and the tier -volumeId
commands resolve the volume's actual collection from topology first so
patterns and named-collection requests pass the volume server's
collection check.
* shell: spell the default-collection keyword via CollectionDefault
* shell: address review findings on collection filter handling
volume.fsck keeps a set of every volume the master knows before any
filtering, so a filer entry whose volume was excluded by -collection or
-volumeId is skipped instead of reported "volume not found" and deleted
by -reallyDeleteFilerEntries. The collection filter also no longer
scopes the filer walk to /buckets/<collection>: fs.configure can bind a
collection to any path prefix, and a narrower walk could mark live
chunks as orphans under -reallyDeleteFromVolume.
ec.rebuild and ec.balance resolve -collection through the new
wildcard.ExpandCollectionFilter, which passes literal names through even
when the master does not list them — ec.rebuild must be able to recover
a collection whose shards all lost their index and never registered.
fs.configure and mq.topic.compact now reject _default outright: an empty
Collection means "unset" in both the path-rule merge and the filer's
storage-option fallback chain, so the keyword would have been silently
ignored.
The unnamed-collection vacuum sweep keeps the master's low-disk-space
exception: a volume whose every replica is read-only is probed with
VacuumVolumeCheck and stays eligible when a replica reports
DiskSpaceLow, instead of being dropped outright.
* shell: say which read-only volumes volume.vacuum leaves alone
volume.vacuum without -volumeId runs the same sweep as the automatic
vacuum, which skips read-only volumes, and the master's response carries
no result. An operator whose disk filled up runs the command, sees it
return, and watches nothing change (issue #11516).
Before issuing the request, list the read-only volumes whose garbage is at
or above the threshold and point at -volumeId, which is the explicit path
PR #9861 opened for them. The help text says the same.
* shell: volume.vacuum hint survives a failed listing and looks at every replica
Review follow-ups: a failed topology listing no longer stops a sweep
without -volumeId, it only drops the hint; a volume counts as read-only
when any replica is, with the garbage ratio taken from the replica that
reports the most, which is what the sweep itself does; a converted index
that reports deletes without sizes is listed rather than hidden; and the
threshold is printed as given instead of rounded to two decimals.
* shell: do not guess a garbage ratio for a converted index
The master cannot compute one for a volume that reports deletes without
their sizes, and a guess of 1 would send the operator to -volumeId for a
volume the server may decline at that threshold. Leave it out and say so.
Chris Lu