kv: don't perform async intent resolution on 1PC with point lock spans

[nvanbenschoten]

Fixes #98571.

This commit fixes the regression detected in #98571. In that issue, we saw that the bug fix in 86a5852 (#98044) caused a regression in kv0 (and other benchmarks). This was due to a bug in kvserverbase.IntersectSpan, which was considering local point spans to be external to the provided range span.

This commit fixes the bug by not calling kvserverbase.IntersectSpan for point lock spans.

The commit also makes the utility panic instead of silently returning incorrect results. There's an existing TODO on the utility to generalize it. For now, we just make it harder to misuse.

Finally, we add a test that asserts against the presence of async intent resolution after one-phase commits when external intent resolution is not needed.

name                            old time/op    new time/op    delta
KV/Insert/Native/rows=1-10        61.2µs ± 3%    48.9µs ± 3%  -20.10%  (p=0.000 n=8+9)
KV/Insert/Native/rows=10-10       93.3µs ±15%    76.2µs ± 3%  -18.34%  (p=0.000 n=9+9)
KV/Insert/Native/rows=1000-10     2.84ms ±12%    2.42ms ± 4%  -14.97%  (p=0.000 n=9+9)
KV/Insert/Native/rows=100-10       365µs ± 5%     320µs ± 8%  -12.40%  (p=0.000 n=10+9)
KV/Insert/Native/rows=10000-10    27.6ms ± 6%    24.4ms ± 3%  -11.53%  (p=0.000 n=9+9)

name                            old alloc/op   new alloc/op   delta
KV/Insert/Native/rows=1000-10     4.66MB ± 1%    2.76MB ± 1%  -40.89%  (p=0.000 n=9+9)
KV/Insert/Native/rows=100-10       478kB ± 1%     287kB ± 1%  -39.90%  (p=0.000 n=10+10)
KV/Insert/Native/rows=10000-10    54.2MB ± 2%    34.3MB ± 3%  -36.73%  (p=0.000 n=10+10)
KV/Insert/Native/rows=10-10       64.2kB ± 1%    42.1kB ± 1%  -34.39%  (p=0.000 n=10+9)
KV/Insert/Native/rows=1-10        22.1kB ± 1%    17.3kB ± 1%  -21.56%  (p=0.000 n=9+10)

name                            old allocs/op  new allocs/op  delta
KV/Insert/Native/rows=1000-10      21.5k ± 0%     14.7k ± 0%  -31.70%  (p=0.000 n=8+9)
KV/Insert/Native/rows=10000-10      212k ± 0%      146k ± 0%  -31.31%  (p=0.000 n=9+10)
KV/Insert/Native/rows=100-10       2.34k ± 1%     1.61k ± 0%  -31.31%  (p=0.000 n=10+10)
KV/Insert/Native/rows=10-10          392 ± 1%       276 ± 0%  -29.59%  (p=0.000 n=8+8)
KV/Insert/Native/rows=1-10           173 ± 1%       123 ± 0%  -29.04%  (p=0.000 n=9+8)

Release note: None

[cockroach-teamcity]

This change is 

[arulajmani]

Reviewed 3 of 3 files at r1, all commit messages.
Reviewable status: complete! 1 of 0 LGTMs obtained (waiting on @nvanbenschoten)

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-- commits line 19 at r1:
Nice!

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pkg/kv/kvserver/replica_write.go line 592 at r1 (raw file):

	var externalLocks []roachpb.Span
	for _, sp := range etArg.LockSpans {
		if len(sp.EndKey) == 0 {

nit: let's add a comment explaining why we're special case handling point locks?

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pkg/kv/kvserver/replica_test.go line 6978 at r1 (raw file):

	for _, tc := range []struct {
		intent   roachpb.Span

Should we rename this to "span" and generalize some of the intent commentary below as well?

[nvanbenschoten]

TFTR!

Reviewable status: complete! 1 of 0 LGTMs obtained (waiting on @arulajmani)

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pkg/kv/kvserver/replica_write.go line 592 at r1 (raw file):

Previously, arulajmani (Arul Ajmani) wrote…

nit: let's add a comment explaining why we're special case handling point locks?

Done.

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pkg/kv/kvserver/replica_test.go line 6978 at r1 (raw file):

Previously, arulajmani (Arul Ajmani) wrote…

Should we rename this to "span" and generalize some of the intent commentary below as well?

Good idea. Done.

[nvanbenschoten]

bors r=arulajmani

[craig]

Build succeeded:

• Bazel Essential CI (Cockroach)