Skip to content

Commit

Permalink
storage: set correct key in WriteTooOld error from pebbleMVCCScanner
Browse files Browse the repository at this point in the history 
Noticed while reviewing cockroachdb#131093.

This commit fixes pebbleMVCCScanner to set the correct key for the
mostRecentKey field when a locking read encounters multiple keys with
more recent timestamps. These keys were added to WriteTooOld error in
52c6b1b, which had previously only been carrying the maximum
conflicting timestamp. They are currently only used for debugging.

Before this fix, we would always return the first conflicting key, even
though we correctly returned the maximum conflicting timestamp.

Epic: None
Release note: None
  • Loading branch information
@nvanbenschoten
nvanbenschoten committed Sep 23, 2024
1 parent ac6239f commit 6a935de
Show file tree
Hide file tree
Showing 4 changed files with 18 additions and 21 deletions.
13 changes: 5 additions & 8 deletions pkg/storage/pebble_mvcc_scanner.go
View file
Original file line number Diff line number Diff line change
Expand Up @@ -850,9 +850,8 @@ func (p *pebbleMVCCScanner) getOne(ctx context.Context) (ok, added bool) {
// timestamp with the maximum timestamp we've seen so we know to
// return an error, but then keep scanning so that we can return
// the largest possible time.
p.mostRecentTS.Forward(p.curUnsafeKey.Timestamp)
if len(p.mostRecentKey) == 0 {
p.mostRecentKey = append(p.mostRecentKey, p.curUnsafeKey.Key...)
if p.mostRecentTS.Forward(p.curUnsafeKey.Timestamp) {
p.mostRecentKey = append(p.mostRecentKey[:0], p.curUnsafeKey.Key...)
}
return true /* ok */, false
}
Expand Down Expand Up @@ -883,9 +882,8 @@ func (p *pebbleMVCCScanner) getOne(ctx context.Context) (ok, added bool) {
// timestamp with the maximum timestamp we've seen so we know to
// return an error, but then keep scanning so that we can return
// the largest possible time.
p.mostRecentTS.Forward(p.curUnsafeKey.Timestamp)
if len(p.mostRecentKey) == 0 {
p.mostRecentKey = append(p.mostRecentKey, p.curUnsafeKey.Key...)
if p.mostRecentTS.Forward(p.curUnsafeKey.Timestamp) {
p.mostRecentKey = append(p.mostRecentKey[:0], p.curUnsafeKey.Key...)
}
return true /* ok */, false
}
Expand Down Expand Up @@ -1521,8 +1519,7 @@ func (p *pebbleMVCCScanner) processRangeKeys(seeked bool, reverse bool) bool {
if p.failOnMoreRecent {
if key := p.parent.UnsafeKey(); !hasPoint || !key.Timestamp.IsEmpty() {
if newest := p.curRangeKeys.Newest(); p.ts.LessEq(newest) {
p.mostRecentTS.Forward(newest)
if len(p.mostRecentKey) == 0 {
if p.mostRecentTS.Forward(newest) {
p.mostRecentKey = append(p.mostRecentKey[:0], key.Key...)
}
}
Expand Down
2 changes: 1 addition & 1 deletion pkg/storage/testdata/mvcc_histories/range_tombstone_scans
View file
Original file line number Diff line number Diff line change
Expand Up @@ -384,7 +384,7 @@ run error
scan k=a end=d ts=3 failOnMoreRecent
----
scan: "a"-"d" -> <no data>
error: (*kvpb.WriteTooOldError:) WriteTooOldError: write for key "a" at timestamp 3.000000000,0 too old; must write at or above 4.000000000,1
error: (*kvpb.WriteTooOldError:) WriteTooOldError: write for key "c" at timestamp 3.000000000,0 too old; must write at or above 4.000000000,1

run error
scan k=a end=d ts=4 failOnMoreRecent
Expand Down
4 changes: 2 additions & 2 deletions pkg/storage/testdata/mvcc_histories/read_fail_on_more_recent
View file
Original file line number Diff line number Diff line change
Expand Up @@ -242,13 +242,13 @@ run error
scan k=a end=b_next ts=9,0 failOnMoreRecent
----
scan: "a"-"b_next" -> <no data>
error: (*kvpb.WriteTooOldError:) WriteTooOldError: write for key "a" at timestamp 9.000000000,0 too old; must write at or above 13.000000000,1
error: (*kvpb.WriteTooOldError:) WriteTooOldError: write for key "b" at timestamp 9.000000000,0 too old; must write at or above 13.000000000,1

run error
scan k=a end=c_next ts=9,0 failOnMoreRecent
----
scan: "a"-"c_next" -> <no data>
error: (*kvpb.WriteTooOldError:) WriteTooOldError: write for key "a" at timestamp 9.000000000,0 too old; must write at or above 13.000000000,1
error: (*kvpb.WriteTooOldError:) WriteTooOldError: write for key "b" at timestamp 9.000000000,0 too old; must write at or above 13.000000000,1

run error
scan k=b end=c_next ts=9,0 failOnMoreRecent
Expand Down
20 changes: 10 additions & 10 deletions pkg/storage/testdata/mvcc_histories/skip_locked
View file
Original file line number Diff line number Diff line change
Expand Up @@ -764,13 +764,13 @@ run error
scan ts=10 k=k1 end=k9 skipLocked failOnMoreRecent str=shared
----
scan: "k1"-"k9" -> <no data>
error: (*kvpb.WriteTooOldError:) WriteTooOldError: write for key "k1" at timestamp 10.000000000,0 too old; must write at or above 17.000000000,1
error: (*kvpb.WriteTooOldError:) WriteTooOldError: write for key "k5" at timestamp 10.000000000,0 too old; must write at or above 17.000000000,1

run error
scan ts=10 k=k1 end=k9 reverse skipLocked failOnMoreRecent str=shared
----
scan: "k1"-"k9" -> <no data>
error: (*kvpb.WriteTooOldError:) WriteTooOldError: write for key "k6" at timestamp 10.000000000,0 too old; must write at or above 17.000000000,1
error: (*kvpb.WriteTooOldError:) WriteTooOldError: write for key "k5" at timestamp 10.000000000,0 too old; must write at or above 17.000000000,1

run error
get ts=11 k=k1 skipLocked failOnMoreRecent str=shared
Expand Down Expand Up @@ -812,13 +812,13 @@ run error
scan ts=11 k=k1 end=k9 skipLocked failOnMoreRecent str=shared
----
scan: "k1"-"k9" -> <no data>
error: (*kvpb.WriteTooOldError:) WriteTooOldError: write for key "k1" at timestamp 11.000000000,0 too old; must write at or above 17.000000000,1
error: (*kvpb.WriteTooOldError:) WriteTooOldError: write for key "k5" at timestamp 11.000000000,0 too old; must write at or above 17.000000000,1

run error
scan ts=11 k=k1 end=k9 reverse skipLocked failOnMoreRecent str=shared
----
scan: "k1"-"k9" -> <no data>
error: (*kvpb.WriteTooOldError:) WriteTooOldError: write for key "k6" at timestamp 11.000000000,0 too old; must write at or above 17.000000000,1
error: (*kvpb.WriteTooOldError:) WriteTooOldError: write for key "k5" at timestamp 11.000000000,0 too old; must write at or above 17.000000000,1

run ok
get ts=12 k=k1 skipLocked failOnMoreRecent str=shared
Expand Down Expand Up @@ -865,7 +865,7 @@ run error
scan ts=12 k=k1 end=k9 reverse skipLocked failOnMoreRecent str=shared
----
scan: "k1"-"k9" -> <no data>
error: (*kvpb.WriteTooOldError:) WriteTooOldError: write for key "k6" at timestamp 12.000000000,0 too old; must write at or above 17.000000000,1
error: (*kvpb.WriteTooOldError:) WriteTooOldError: write for key "k5" at timestamp 12.000000000,0 too old; must write at or above 17.000000000,1

run ok
get ts=12 t=A k=k1 skipLocked failOnMoreRecent str=shared
Expand Down Expand Up @@ -912,7 +912,7 @@ run error
scan ts=12 t=A k=k1 end=k9 reverse skipLocked failOnMoreRecent str=shared
----
scan: "k1"-"k9" -> <no data>
error: (*kvpb.WriteTooOldError:) WriteTooOldError: write for key "k6" at timestamp 12.000000000,0 too old; must write at or above 17.000000000,1
error: (*kvpb.WriteTooOldError:) WriteTooOldError: write for key "k5" at timestamp 12.000000000,0 too old; must write at or above 17.000000000,1

run ok
get ts=13 k=k1 skipLocked failOnMoreRecent str=shared
Expand Down Expand Up @@ -959,7 +959,7 @@ run error
scan ts=13 k=k1 end=k9 reverse skipLocked failOnMoreRecent str=shared
----
scan: "k1"-"k9" -> <no data>
error: (*kvpb.WriteTooOldError:) WriteTooOldError: write for key "k6" at timestamp 13.000000000,0 too old; must write at or above 17.000000000,1
error: (*kvpb.WriteTooOldError:) WriteTooOldError: write for key "k5" at timestamp 13.000000000,0 too old; must write at or above 17.000000000,1

run ok
get ts=13 t=B k=k1 skipLocked failOnMoreRecent str=shared
Expand Down Expand Up @@ -1005,7 +1005,7 @@ run error
scan ts=13 t=B k=k1 end=k9 reverse skipLocked failOnMoreRecent str=shared
----
scan: "k1"-"k9" -> <no data>
error: (*kvpb.WriteTooOldError:) WriteTooOldError: write for key "k6" at timestamp 13.000000000,0 too old; must write at or above 17.000000000,1
error: (*kvpb.WriteTooOldError:) WriteTooOldError: write for key "k5" at timestamp 13.000000000,0 too old; must write at or above 17.000000000,1

run ok
get ts=14 k=k1 skipLocked failOnMoreRecent str=shared
Expand Down Expand Up @@ -1424,7 +1424,7 @@ run error
scan ts=10 k=k1 end=k9 skipLocked failOnMoreRecent str=exclusive
----
scan: "k1"-"k9" -> <no data>
error: (*kvpb.WriteTooOldError:) WriteTooOldError: write for key "k1" at timestamp 10.000000000,0 too old; must write at or above 17.000000000,1
error: (*kvpb.WriteTooOldError:) WriteTooOldError: write for key "k5" at timestamp 10.000000000,0 too old; must write at or above 17.000000000,1

run error
scan ts=10 k=k1 end=k9 reverse skipLocked failOnMoreRecent str=exclusive
Expand Down Expand Up @@ -1472,7 +1472,7 @@ run error
scan ts=11 k=k1 end=k9 skipLocked failOnMoreRecent str=exclusive
----
scan: "k1"-"k9" -> <no data>
error: (*kvpb.WriteTooOldError:) WriteTooOldError: write for key "k1" at timestamp 11.000000000,0 too old; must write at or above 17.000000000,1
error: (*kvpb.WriteTooOldError:) WriteTooOldError: write for key "k5" at timestamp 11.000000000,0 too old; must write at or above 17.000000000,1

run error
scan ts=11 k=k1 end=k9 reverse skipLocked failOnMoreRecent str=exclusive
Expand Down

0 comments on commit 6a935de

Please sign in to comment.