sql: add query level stats to EXPLAIN ANALYZE

[RaduBerinde]

This change adds top-level query stats to the EXPLAIN ANALYZE output.

Release note (sql change): EXPLAIN ANALYZE now shows more top-level
query statistics.

[cockroach-teamcity]

This change is 

[RaduBerinde]

I am unsure of the max-memory and network usage stats. Do we think these are currently robust enough to be useful? I could hide them behind the VERBOSE flag if not.

[awoods187]

Could you post some examples for the issue?

I am unsure of the max-memory and network usage stats. Do we think these are currently robust enough to be useful?

I'd vote in favor of adding them to Explain Analyze.

[RaduBerinde]

Example:

demo@127.0.0.1:26257/movr> EXPLAIN ANALYZE SELECT * FROM rides JOIN vehicles ON rides.vehicle_id
= vehicles.id; 
                    info
--------------------------------------------
  planning time: 530µs
  execution time: 5ms
  distribution: full
  vectorized: true
  rows read from KV: 515 (89 KiB)
  cumulative time spent in KV: 3ms
  maximum memory usage: 566 KiB
  network usage: 0 B (0 messages)

  • hash join
  │ actual row count: 500
  │ equality: (vehicle_id) = (id)
  │
  ├── • scan
  │     actual row count: 500
  │     KV rows read: 500
  │     KV bytes read: 86 KiB
  │     missing stats
  │     table: rides@primary
  │     spans: FULL SCAN
  │
  └── • scan
        actual row count: 15
        KV rows read: 15
        KV bytes read: 2.3 KiB
        missing stats
        table: vehicles@primary
        spans: FULL SCAN

  WARNING: this statement is experimental!
(30 rows)

Time: 6ms total (execution 5ms / network 0ms)

I'd vote in favor of adding them to Explain Analyze.

Any thoughts on whether any of it should be VERBOSE-only?

[awoods187]

I love it! I'd vote to keep them in EXPLAIN ANALYZE and not in a verbose only mode.

[asubiotto]

I'm in agreement with Andy. It might not be useful in some cases but I think it's better to show more than less information (users might not even know there is a verbose mode) and iterate from there if we get negative feedback.

Reviewed 13 of 13 files at r1.
Reviewable status: complete! 0 of 0 LGTMs obtained (waiting on @RaduBerinde)

---

pkg/sql/explain_plan.go, line 174 at r1 (raw file):

	if explainPlan == nil {
		return errors.New("no plan")

Is there enough context to understand this error?

---

pkg/sql/instrumentation.go, line 262 at r1 (raw file):

			stmtStats.mu.Unlock()
		}
		txnStats.Accumulate(queryLevelStats)

I'm not sure we want to call Accumulate outside the block. Might lead to cases where stats don't add up in the DB console (i.e. one statement in a txn has nil stmt stats but what was collected is reflected in the txn stats).

---

pkg/sql/logictest/testdata/logic_test/explain_analyze, line 39 at r1 (raw file):

distribution: <hidden>
vectorized: <hidden>
rows read from KV: 3 (24 B)

Are the bytes values deterministic?

[RaduBerinde]

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

---

pkg/sql/explain_plan.go, line 174 at r1 (raw file):

Previously, asubiotto (Alfonso Subiotto Marqués) wrote…

Is there enough context to understand this error?

We are checking at a higher level, this is a "just in case" check (I ran into a NPE while working on this change). In general, no plan means that there was an error during planning. Changed to an AssertionFailedf.

---

pkg/sql/instrumentation.go, line 262 at r1 (raw file):

Previously, asubiotto (Alfonso Subiotto Marqués) wrote…

I'm not sure we want to call Accumulate outside the block. Might lead to cases where stats don't add up in the DB console (i.e. one statement in a txn has nil stmt stats but what was collected is reflected in the txn stats).

Done.

---

pkg/sql/logictest/testdata/logic_test/explain_analyze, line 39 at r1 (raw file):

Previously, asubiotto (Alfonso Subiotto Marqués) wrote…

Are the bytes values deterministic?

Yeah, 8 per row

[RaduBerinde]

bors r+

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

[craig]

Build failed (retrying...):

• GitHub CI (Cockroach)

[craig]

Build succeeded:

• GitHub CI (Cockroach)