metamorphic: add lazy load SeekPrefixGE opt

[Sachuman]

metamorphic: add lazy load SeekPrefixGE opt

This commit enables new lazy load optimization (maxsuffixprop) on metamorphic test
with probability of 20%

Part of #2002
Previous #5256

[cockroach-teamcity]

This change is 

[jbowens]

looking good!

Read up to the metamorphic test commit but not the last commit. I have some suggestions on the metamorphic test integration. If you want, you can pull the other commits out into separate PRs to get them merged earlier

@jbowens reviewed 1 of 1 files at r1, 9 of 9 files at r9, 9 of 9 files at r10, 2 of 7 files at r11.
Reviewable status: 3 of 10 files reviewed, 8 unresolved discussions (waiting on @xxmplus)

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metamorphic/config.go line 445 at r11 (raw file):

	// MaximumSuffixProperty returns the maximum suffix property used during
	// the lazy position of SeekPrefixGE optimization.
	MaximumSuffixProperty() pebble.MaximumSuffixProperty

instead of putting this on the generator, I think this should be a field on the KeyFormat in metamorphic/config.go

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cockroachkvs/blockproperties.go line 151 at r9 (raw file):

type MaxMVCCTimestampProperty struct{}

// Name is part of the cockroachkvs.MaxMVCCTimestampProperty interface.

nit: let's say "Name implements the pebble.MaximumSuffixProperty interface."

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cockroachkvs/blockproperties.go line 156 at r9 (raw file):

}

// Extract is part of the cockroachkvs.MaxMVCCTimestampProperty interface.

s/Extract implements the pebble.MaximumSuffixProperty interface./

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cockroachkvs/blockproperties.go line 170 at r9 (raw file):

		return nil, false, nil
	}
	// Decode the block interval using the same logic as sstable.decodeBlockInterval

nit: I think we should export sstable.DecodeBlockInterval and call it here since we're tightly coupled to the sstable's block interval property encoding

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cockroachkvs/blockproperties.go line 193 at r9 (raw file):

	dst = append(dst, make([]byte, 9)...)
	binary.BigEndian.PutUint64(dst[len(dst)-9:], interval.Upper)
	dst[len(dst)-1] = 9

nit: instead of inlining 9, let's use suffixLenWithWall

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sstable/reader_iter_two_lvl.go line 470 at r10 (raw file):

		// the top of the iterator's heap, and the iterator is Nexted.
		// During a RangeDelIter, the prefix passed and the prefix in the key might not be the same.
		if ok && maxSuffix != nil && i.secondLevel.reader.Comparer.ComparePointSuffixes(key[len(i.secondLevel.reader.Comparer.Split.Prefix(key)):], maxSuffix) < 0 {

ditto: regarding calling Split directly

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sstable/reader_iter_single_lvl.go line 867 at r10 (raw file):

		// the top of the iterator's heap, and the iterator is Nexted.
		// During a RangeDelIter, the prefix passed and the prefix in the key might not be the same.
		if ok && maxSuffix != nil && i.reader.Comparer.ComparePointSuffixes(key[len(i.reader.Comparer.Split.Prefix(key)):], maxSuffix) < 0 {

nit: to extract the suffix index, we can just call Split directly like:key[i.reader.Comparer.Split(key):]

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metamorphic/ops.go line 581 at r11 (raw file):

}

func deserializeMaximumSuffixProperty(s string) pebble.MaximumSuffixProperty {

rather than serializing the name of the implementation, I think we just serialize "maxsuffixprop" vs "none"; then when MaximumSuffixProperty we use can be determined by the KeyFormat used by the test

[Sachuman]

Done.

Reviewable status: 0 of 14 files reviewed, 8 unresolved discussions (waiting on @jbowens and @xxmplus)

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metamorphic/config.go line 445 at r11 (raw file):

Previously, jbowens (Jackson Owens) wrote…

instead of putting this on the generator, I think this should be a field on the KeyFormat in metamorphic/config.go

Done.

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metamorphic/ops.go line 581 at r11 (raw file):

Previously, jbowens (Jackson Owens) wrote…

rather than serializing the name of the implementation, I think we just serialize "maxsuffixprop" vs "none"; then when MaximumSuffixProperty we use can be determined by the KeyFormat used by the test

Done.