Add tracing spans for pipeline and transaction functions

[adam-fowler]

This add tracing spans for the pipeline and transaction functions. Span name is either Pipeline or MULTI. The database operation name though is a list of the commands concatenated together eg SET,SET,INCR.

None of the functions report errors for individual commands as the Results returned by the commands are not processed and processing them would add additional The pipeline functions don't report errors as it doesn't process errors it only returns a collection of Results. The transaction functions report errors returned by EXEC but again errors from individual commands are not reported.

@slashmo

[github-actions]

✅ Pull request has performance improvements ✅

Summary

==============================================================================
Threshold deviations for ValkeyBenchmarks:Connection: Pipeline array benchmark
==============================================================================

Malloc (total) (K, %)	main	pull_request	Difference %	Threshold %
p25	20	17	-14	5

New baseline 'pull_request' is BETTER than the 'main' baseline thresholds.

Full Benchmark Comparison

Comparing results between 'main' and 'pull_request'

Host '9ef60a476605' with 4 'x86_64' processors with 15 GB memory, running:
#18~24.04.1-Ubuntu SMP Sat Jun 28 04:46:03 UTC 2025

ValkeyBenchmarks

Client: GET benchmark metrics

Malloc (total): results within specified thresholds, fold down for details.

Malloc (total) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	52	52	53	55	56	56	56	6
pull_request	50	51	54	56	56	56	56	6
Δ	-2	-1	1	1	0	0	0	0
Improvement %	4	2	-2	-2	0	0	0	0

Client: GET benchmark | parallel 20 | 20 concurrent connections metrics

Malloc (total): results within specified thresholds, fold down for details.

Malloc (total) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	46	53	54	57	59	62	62	24
pull_request	49	53	55	56	58	64	64	28
Δ	3	0	1	-1	-1	2	2	4
Improvement %	-7	0	-2	2	2	-3	-3	4

Connection: GET benchmark metrics

Malloc (total): results within specified thresholds, fold down for details.

Malloc (total) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	4	4	4	4	4	4	4	8
pull_request	4	4	4	4	4	4	4	8
Δ	0	0	0	0	0	0	0	0
Improvement %	0	0	0	0	0	0	0	0

Connection: GET benchmark – NoOpTracer metrics

Malloc (total): results within specified thresholds, fold down for details.

Malloc (total) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	4	7	8	9	9	9	9	8
pull_request	4	7	8	9	9	9	9	8
Δ	0	0	0	0	0	0	0	0
Improvement %	0	0	0	0	0	0	0	0

Connection: Pipeline array benchmark metrics

Malloc (total): results within specified thresholds, fold down for details.

Malloc (total) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	9	20	24	26	27	27	27	7
pull_request	9	17	24	26	27	27	27	7
Δ	0	-3	0	0	0	0	0	0
Improvement %	0	15	0	0	0	0	0	0

Connection: Pipeline benchmark metrics

Malloc (total): results within specified thresholds, fold down for details.

Malloc (total) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	7	24	24	25	25	25	25	7
pull_request	7	24	24	25	25	25	25	7
Δ	0	0	0	0	0	0	0	0
Improvement %	0	0	0	0	0	0	0	0

HashSlot – {user}.whatever metrics

Malloc (total): results within specified thresholds, fold down for details.

Malloc (total) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	0	0	0	0	0	0	0	19
pull_request	0	0	0	0	0	0	0	19
Δ	0	0	0	0	0	0	0	0
Improvement %	0	0	0	0	0	0	0	0

ValkeyCommandEncoder – Command with 7 words metrics

Malloc (total): results within specified thresholds, fold down for details.

Malloc (total) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	0	0	0	0	0	0	0	830
pull_request	0	0	0	0	0	0	0	832
Δ	0	0	0	0	0	0	0	2
Improvement %	0	0	0	0	0	0	0	2

ValkeyCommandEncoder – Simple GET metrics

Malloc (total): results within specified thresholds, fold down for details.

Malloc (total) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	0	0	0	0	0	0	0	1987
pull_request	0	0	0	0	0	0	0	2011
Δ	0	0	0	0	0	0	0	24
Improvement %	0	0	0	0	0	0	0	24

ValkeyCommandEncoder – Simple MGET 15 keys metrics

Malloc (total): results within specified thresholds, fold down for details.

Malloc (total) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	0	0	0	0	0	0	0	375
pull_request	0	0	0	0	0	0	0	374
Δ	0	0	0	0	0	0	0	-1
Improvement %	0	0	0	0	0	0	0	-1

[nilanshu-sharma]

Should we also add databaseNumber here as well for better tracing ?

[adam-fowler]

There's not an obvious Otel parameter to use for database number. See https://opentelemetry.io/docs/specs/semconv/registry/attributes/db/

[nilanshu-sharma]

Added comments.

[nilanshu-sharma]

Looks good to me!