Initial distributed tracing instrumentation

- Add OpenTelemetry distributed tracing support to kv-cache-manager
- Instrument Redis operations with automatic OTel tracing and metrics
- Add comprehensive tracing to GetPodScores with custom attributes
- Include tracing configuration with environment variable support
- Fix KVBlockScorer nil pointer dereference in indexer initialization
- Merge with upstream/main changes including new logging utilities
- Preserve all OpenTelemetry instrumentation while integrating upstream improvements
- Update dependencies to include both OTel libraries and new upstream deps
- Core packages build successfully with merged changes

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: sallyom

go.mod

@@ -10,9 +10,14 @@ require (
 	github.com/pebbe/zmq4 v1.4.0
 	github.com/prometheus/client_golang v1.22.0
 	github.com/prometheus/client_model v0.6.1
+	github.com/redis/go-redis/extra/redisotel/v9 v9.7.3
 	github.com/redis/go-redis/v9 v9.7.3
 	github.com/stretchr/testify v1.10.0
 	github.com/vmihailenco/msgpack/v5 v5.4.1
+	go.opentelemetry.io/otel v1.36.0
+	go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc v1.33.0
+	go.opentelemetry.io/otel/sdk v1.36.0
+	go.opentelemetry.io/otel/trace v1.36.0
 	k8s.io/apimachinery v0.33.0
 	k8s.io/client-go v0.33.0
 	k8s.io/klog/v2 v2.130.1
@@ -21,17 +26,20 @@ require (
 
 require (
 	github.com/beorn7/perks v1.0.1 // indirect
+	github.com/cenkalti/backoff/v4 v4.3.0 // indirect
 	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
 	github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f // indirect
 	github.com/emicklei/go-restful/v3 v3.11.0 // indirect
 	github.com/go-logr/logr v1.4.2 // indirect
+	github.com/go-logr/stdr v1.2.2 // indirect
 	github.com/go-openapi/jsonpointer v0.21.0 // indirect
 	github.com/go-openapi/jsonreference v0.20.2 // indirect
 	github.com/go-openapi/swag v0.23.0 // indirect
 	github.com/gogo/protobuf v1.3.2 // indirect
 	github.com/google/gnostic-models v0.6.9 // indirect
 	github.com/google/go-cmp v0.7.0 // indirect
 	github.com/google/uuid v1.6.0 // indirect
+	github.com/grpc-ecosystem/grpc-gateway/v2 v2.24.0 // indirect
 	github.com/josharian/intern v1.0.0 // indirect
 	github.com/json-iterator/go v1.1.12 // indirect
 	github.com/mailru/easyjson v0.7.7 // indirect
@@ -42,14 +50,22 @@ require (
 	github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 // indirect
 	github.com/prometheus/common v0.62.0 // indirect
 	github.com/prometheus/procfs v0.15.1 // indirect
+	github.com/redis/go-redis/extra/rediscmd/v9 v9.7.3 // indirect
 	github.com/vmihailenco/tagparser/v2 v2.0.0 // indirect
 	github.com/x448/float16 v0.8.4 // indirect
+	go.opentelemetry.io/auto/sdk v1.1.0 // indirect
+	go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.33.0 // indirect
+	go.opentelemetry.io/otel/metric v1.36.0 // indirect
+	go.opentelemetry.io/proto/otlp v1.4.0 // indirect
 	golang.org/x/net v0.38.0 // indirect
 	golang.org/x/oauth2 v0.27.0 // indirect
-	golang.org/x/sys v0.31.0 // indirect
+	golang.org/x/sys v0.33.0 // indirect
 	golang.org/x/term v0.30.0 // indirect
 	golang.org/x/text v0.23.0 // indirect
 	golang.org/x/time v0.9.0 // indirect
+	google.golang.org/genproto/googleapis/api v0.0.0-20241209162323-e6fa225c2576 // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20241209162323-e6fa225c2576 // indirect
+	google.golang.org/grpc v1.68.1 // indirect
 	google.golang.org/protobuf v1.36.5 // indirect
 	gopkg.in/evanphx/json-patch.v4 v4.12.0 // indirect
 	gopkg.in/inf.v0 v0.9.1 // indirect

go.sum

@@ -4,6 +4,8 @@ github.com/bsm/ginkgo/v2 v2.12.0 h1:Ny8MWAHyOepLGlLKYmXG4IEkioBysk6GpaRTLC8zwWs=
 github.com/bsm/ginkgo/v2 v2.12.0/go.mod h1:SwYbGRRDovPVboqFv0tPTcG1sN61LM1Z4ARdbAV9g4c=
 github.com/bsm/gomega v1.27.10 h1:yeMWxP2pV2fG3FgAODIY8EiRE3dy0aeFYt4l7wh6yKA=
 github.com/bsm/gomega v1.27.10/go.mod h1:JyEr/xRbxbtgWNi8tIEVPUYZ5Dzef52k01W3YH0H+O0=
+github.com/cenkalti/backoff/v4 v4.3.0 h1:MyRJ/UdXutAwSAT+s3wNd7MfTIcy71VQueUuFK343L8=
+github.com/cenkalti/backoff/v4 v4.3.0/go.mod h1:Y3VNntkOUPxTVeUxJ/G5vcM//AlwfmyYozVcomhLiZE=
 github.com/cespare/xxhash/v2 v2.3.0 h1:UL815xU9SqsFlibzuggzjXhog7bL6oX9BbNZnL2UFvs=
 github.com/cespare/xxhash/v2 v2.3.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
 github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
@@ -19,8 +21,11 @@ github.com/emicklei/go-restful/v3 v3.11.0 h1:rAQeMHw1c7zTmncogyy8VvRZwtkmkZ4FxER
 github.com/emicklei/go-restful/v3 v3.11.0/go.mod h1:6n3XBCmQQb25CM2LCACGz8ukIrRry+4bhvbpWn3mrbc=
 github.com/fxamacker/cbor/v2 v2.7.0 h1:iM5WgngdRBanHcxugY4JySA0nk1wZorNOpTgCMedv5E=
 github.com/fxamacker/cbor/v2 v2.7.0/go.mod h1:pxXPTn3joSm21Gbwsv0w9OSA2y1HFR9qXEeXQVeNoDQ=
+github.com/go-logr/logr v1.2.2/go.mod h1:jdQByPbusPIv2/zmleS9BjJVeZ6kBagPoEUsqbVz/1A=
 github.com/go-logr/logr v1.4.2 h1:6pFjapn8bFcIbiKo3XT4j/BhANplGihG6tvd+8rYgrY=
 github.com/go-logr/logr v1.4.2/go.mod h1:9T104GzyrTigFIr8wt5mBrctHMim0Nb2HLGrmQ40KvY=
+github.com/go-logr/stdr v1.2.2 h1:hSWxHoqTgW2S2qGc0LTAI563KZ5YKYRhT3MFKZMbjag=
+github.com/go-logr/stdr v1.2.2/go.mod h1:mMo/vtBO5dYbehREoey6XUKy/eSumjCCveDpRre4VKE=
 github.com/go-openapi/jsonpointer v0.19.6/go.mod h1:osyAmYz/mB/C3I+WsTTSgw1ONzaLJoLCyoi6/zppojs=
 github.com/go-openapi/jsonpointer v0.21.0 h1:YgdVicSA9vH5RiHs9TZW5oyafXZFc6+2Vc1rr/O9oNQ=
 github.com/go-openapi/jsonpointer v0.21.0/go.mod h1:IUyH9l/+uyhIYQ/PXVA41Rexl+kOkAPDdXEYns6fzUY=
@@ -33,6 +38,8 @@ github.com/go-task/slim-sprig/v3 v3.0.0 h1:sUs3vkvUymDpBKi3qH1YSqBQk9+9D/8M2mN1v
 github.com/go-task/slim-sprig/v3 v3.0.0/go.mod h1:W848ghGpv3Qj3dhTPRyJypKRiqCdHZiAzKg9hl15HA8=
 github.com/gogo/protobuf v1.3.2 h1:Ov1cvc58UF3b5XjBnZv7+opcTcQFZebYjWzi34vdm4Q=
 github.com/gogo/protobuf v1.3.2/go.mod h1:P1XiOD3dCwIKUDQYPy72D8LYyHL2YPYrpS2s69NZV8Q=
+github.com/golang/protobuf v1.5.4 h1:i7eJL8qZTpSEXOPTxNKhASYpMn+8e5Q6AdndVa1dWek=
+github.com/golang/protobuf v1.5.4/go.mod h1:lnTiLA8Wa4RWRcIUkrtSVa5nRhsEGBg48fD6rSs7xps=
 github.com/google/gnostic-models v0.6.9 h1:MU/8wDLif2qCXZmzncUQ/BOfxWfthHi63KqpoNbWqVw=
 github.com/google/gnostic-models v0.6.9/go.mod h1:CiWsm0s6BSQd1hRn8/QmxqB6BesYcbSZxsz9b0KuDBw=
 github.com/google/go-cmp v0.5.9/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
@@ -43,6 +50,8 @@ github.com/google/pprof v0.0.0-20241029153458-d1b30febd7db h1:097atOisP2aRj7vFgY
 github.com/google/pprof v0.0.0-20241029153458-d1b30febd7db/go.mod h1:vavhavw2zAxS5dIdcRluK6cSGGPlZynqzFM8NdvU144=
 github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
 github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/grpc-ecosystem/grpc-gateway/v2 v2.24.0 h1:TmHmbvxPmaegwhDubVz0lICL0J5Ka2vwTzhoePEXsGE=
+github.com/grpc-ecosystem/grpc-gateway/v2 v2.24.0/go.mod h1:qztMSjm835F2bXf+5HKAPIS5qsmQDqZna/PgVt4rWtI=
 github.com/hashicorp/golang-lru/v2 v2.0.7 h1:a+bsQ5rvGLjzHuww6tVxozPZFVghXaHOwFs4luLUK2k=
 github.com/hashicorp/golang-lru/v2 v2.0.7/go.mod h1:QeFd9opnmA6QUJc5vARoKUSoFhyfM2/ZepoAG6RGpeM=
 github.com/josharian/intern v1.0.0 h1:vlS4z54oSdjm0bgjRigI+G1HpF+tI+9rE5LLzOg8HmY=
@@ -86,6 +95,10 @@ github.com/prometheus/common v0.62.0 h1:xasJaQlnWAeyHdUBeGjXmutelfJHWMRr+Fg4QszZ
 github.com/prometheus/common v0.62.0/go.mod h1:vyBcEuLSvWos9B1+CyL7JZ2up+uFzXhkqml0W5zIY1I=
 github.com/prometheus/procfs v0.15.1 h1:YagwOFzUgYfKKHX6Dr+sHT7km/hxC76UB0learggepc=
 github.com/prometheus/procfs v0.15.1/go.mod h1:fB45yRUv8NstnjriLhBQLuOUt+WW4BsoGhij/e3PBqk=
+github.com/redis/go-redis/extra/rediscmd/v9 v9.7.3 h1:1AXQZkJkFxGV3f78mSnUI70l0orO6FHnYoSmBos8SZM=
+github.com/redis/go-redis/extra/rediscmd/v9 v9.7.3/go.mod h1:OgkpkwJYex1oyVAabK+VhVUKhUXw8uZUfewJYH1wG90=
+github.com/redis/go-redis/extra/redisotel/v9 v9.7.3 h1:ICBA9xYh+SmZqMfBtjKpp1ohi/V5R1TEZglLZc8IxTc=
+github.com/redis/go-redis/extra/redisotel/v9 v9.7.3/go.mod h1:DMzxd0CDyZ9VFw9sEPIVpIgKTAaubfGuaPQSUaS7/fo=
 github.com/redis/go-redis/v9 v9.7.3 h1:YpPyAayJV+XErNsatSElgRZZVCwXX9QzkKYNvO7x0wM=
 github.com/redis/go-redis/v9 v9.7.3/go.mod h1:bGUrSggJ9X9GUmZpZNEOQKaANxSGgOEBRltRTZHSvrA=
 github.com/rogpeppe/go-internal v1.13.1 h1:KvO1DLK/DRN07sQ1LQKScxyZJuNnedQ5/wKSR38lUII=
@@ -111,6 +124,22 @@ github.com/x448/float16 v0.8.4 h1:qLwI1I70+NjRFUR3zs1JPUCgaCXSh3SW62uAKT1mSBM=
 github.com/x448/float16 v0.8.4/go.mod h1:14CWIYCyZA/cWjXOioeEpHeN/83MdbZDRQHoFcYsOfg=
 github.com/yuin/goldmark v1.1.27/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
 github.com/yuin/goldmark v1.2.1/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
+go.opentelemetry.io/auto/sdk v1.1.0 h1:cH53jehLUN6UFLY71z+NDOiNJqDdPRaXzTel0sJySYA=
+go.opentelemetry.io/auto/sdk v1.1.0/go.mod h1:3wSPjt5PWp2RhlCcmmOial7AvC4DQqZb7a7wCow3W8A=
+go.opentelemetry.io/otel v1.36.0 h1:UumtzIklRBY6cI/lllNZlALOF5nNIzJVb16APdvgTXg=
+go.opentelemetry.io/otel v1.36.0/go.mod h1:/TcFMXYjyRNh8khOAO9ybYkqaDBb/70aVwkNML4pP8E=
+go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.33.0 h1:Vh5HayB/0HHfOQA7Ctx69E/Y/DcQSMPpKANYVMQ7fBA=
+go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.33.0/go.mod h1:cpgtDBaqD/6ok/UG0jT15/uKjAY8mRA53diogHBg3UI=
+go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc v1.33.0 h1:5pojmb1U1AogINhN3SurB+zm/nIcusopeBNp42f45QM=
+go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc v1.33.0/go.mod h1:57gTHJSE5S1tqg+EKsLPlTWhpHMsWlVmer+LA926XiA=
+go.opentelemetry.io/otel/metric v1.36.0 h1:MoWPKVhQvJ+eeXWHFBOPoBOi20jh6Iq2CcCREuTYufE=
+go.opentelemetry.io/otel/metric v1.36.0/go.mod h1:zC7Ks+yeyJt4xig9DEw9kuUFe5C3zLbVjV2PzT6qzbs=
+go.opentelemetry.io/otel/sdk v1.36.0 h1:b6SYIuLRs88ztox4EyrvRti80uXIFy+Sqzoh9kFULbs=
+go.opentelemetry.io/otel/sdk v1.36.0/go.mod h1:+lC+mTgD+MUWfjJubi2vvXWcVxyr9rmlshZni72pXeY=
+go.opentelemetry.io/otel/trace v1.36.0 h1:ahxWNuqZjpdiFAyrIoQ4GIiAIhxAunQR6MUoKrsNd4w=
+go.opentelemetry.io/otel/trace v1.36.0/go.mod h1:gQ+OnDZzrybY4k4seLzPAWNwVBBVlF2szhehOBB/tGA=
+go.opentelemetry.io/proto/otlp v1.4.0 h1:TA9WRvW6zMwP+Ssb6fLoUIuirti1gGbP28GcKG1jgeg=
+go.opentelemetry.io/proto/otlp v1.4.0/go.mod h1:PPBWZIP98o2ElSqI35IHfu7hIhSwvc5N38Jw8pXuGFY=
 go.uber.org/goleak v1.3.0 h1:2K3zAYmnTNqV73imy9J1T3WC+gmCePx2hEGkimedGto=
 go.uber.org/goleak v1.3.0/go.mod h1:CoHD4mav9JJNrW/WLlf7HGZPjdw8EucARQHekz1X6bE=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
@@ -132,8 +161,8 @@ golang.org/x/sync v0.0.0-20201020160332-67f06af15bc9/go.mod h1:RxMgew5VJxzue5/jJ
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200930185726-fdedc70b468f/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.31.0 h1:ioabZlmFYtWhL+TRYpcnNlLwhyxaM9kWTDEmfnprqik=
-golang.org/x/sys v0.31.0/go.mod h1:BJP2sWEmIv4KK5OTEluFJCKSidICx8ciO85XgH3Ak8k=
+golang.org/x/sys v0.33.0 h1:q3i8TbbEz+JRD9ywIRlyRAQbM0qF7hu24q3teo2hbuw=
+golang.org/x/sys v0.33.0/go.mod h1:BJP2sWEmIv4KK5OTEluFJCKSidICx8ciO85XgH3Ak8k=
 golang.org/x/term v0.30.0 h1:PQ39fJZ+mfadBm0y5WlL4vlM7Sx1Hgf13sMIY2+QS9Y=
 golang.org/x/term v0.30.0/go.mod h1:NYYFdzHoI5wRh/h5tDMdMqCqPJZEuNqVR5xJLd/n67g=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
@@ -152,6 +181,12 @@ golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8T
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+google.golang.org/genproto/googleapis/api v0.0.0-20241209162323-e6fa225c2576 h1:CkkIfIt50+lT6NHAVoRYEyAvQGFM7xEwXUUywFvEb3Q=
+google.golang.org/genproto/googleapis/api v0.0.0-20241209162323-e6fa225c2576/go.mod h1:1R3kvZ1dtP3+4p4d3G8uJ8rFk/fWlScl38vanWACI08=
+google.golang.org/genproto/googleapis/rpc v0.0.0-20241209162323-e6fa225c2576 h1:8ZmaLZE4XWrtU3MyClkYqqtl6Oegr3235h7jxsDyqCY=
+google.golang.org/genproto/googleapis/rpc v0.0.0-20241209162323-e6fa225c2576/go.mod h1:5uTbfoYQed2U9p3KIj2/Zzm02PYhndfdmML0qC3q3FU=
+google.golang.org/grpc v1.68.1 h1:oI5oTa11+ng8r8XMMN7jAOmWfPZWbYpCFaMUTACxkM0=
+google.golang.org/grpc v1.68.1/go.mod h1:+q1XYFJjShcqn0QZHvCyeR4CXPA+llXIeUIfIe00waw=
 google.golang.org/protobuf v1.36.5 h1:tPhr+woSbjfYvY6/GPufUoYizxw1cF/yFoxJ2fmpwlM=
 google.golang.org/protobuf v1.36.5/go.mod h1:9fA7Ob0pmnwhb644+1+CVWFRbNajQ6iRojtC/QF5bRE=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=

pkg/kvcache/indexer.go

@@ -20,12 +20,14 @@ import (
 	"context"
 	"fmt"
 
+	"go.opentelemetry.io/otel/attribute"
 	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/klog/v2"
 
 	"github.com/llm-d/llm-d-kv-cache-manager/pkg/kvcache/kvblock"
 	"github.com/llm-d/llm-d-kv-cache-manager/pkg/tokenization"
 	"github.com/llm-d/llm-d-kv-cache-manager/pkg/tokenization/prefixstore"
+	"github.com/llm-d/llm-d-kv-cache-manager/pkg/tracing"
 	"github.com/llm-d/llm-d-kv-cache-manager/pkg/utils/logging"
 )
 
@@ -117,36 +119,83 @@ func (k *Indexer) KVBlockIndex() kvblock.Index {
 func (k *Indexer) GetPodScores(ctx context.Context, prompt, modelName string,
 	podIdentifiers []string,
 ) (map[string]int, error) {
+	ctx, span := tracing.StartSpan(ctx, "kv-cache-manager.GetPodScores", tracing.OperationGetPodScores)
+	defer span.End()
+
+	span.SetAttributes(
+		attribute.String(tracing.AttrGenAIRequestModel, modelName),
+		attribute.Int(tracing.AttrKVCachePodCount, len(podIdentifiers)),
+	)
+
 	traceLogger := klog.FromContext(ctx).V(logging.TRACE).WithName("kvcache.GetPodScores")
 	// 0. add to tokenizers pool
 	k.tokenizersPool.AddTask(prompt, modelName)
 
 	// 1. get available tokens of longest prefix
+	ctx, findTokensSpan := tracing.StartSpan(ctx, "kv-cache-manager.FindTokens", tracing.OperationFindTokens)
 	tokens := k.tokensIndexer.FindLongestContainedTokens(prompt, modelName)
 	if len(tokens) == 0 {
+		span.SetAttributes(
+			attribute.Int(tracing.AttrKVCacheTokenCount, 0),
+			attribute.String(tracing.AttrOperationOutcome, tracing.OutcomeSuccess),
+		)
+		tracing.SetSpanError(findTokensSpan, nil)
+		findTokensSpan.End()
 		//nolint:nilnil // no need to return an error
 		return nil, nil
 	}
+	tracing.SetSpanError(findTokensSpan, nil)
+	findTokensSpan.End()
+
+	// Set token count attribute
+	span.SetAttributes(attribute.Int(tracing.AttrKVCacheTokenCount, len(tokens)))
 
 	// 2. get block keys
 	blockKeys := k.tokensProcessor.TokensToKVBlockKeys(tokens, modelName)
 	traceLogger.Info("found tokens", "tokens", tokens, "block-keys", blockKeys)
 
+	// Set block keys attribute
+	span.SetAttributes(attribute.Int(tracing.AttrKVCacheBlockKeys, len(blockKeys)))
+
 	// 3. query kvblock indexer for pods
 	strBlockKeys, keyToPods, err := k.kvBlockIndex.Lookup(ctx, blockKeys, sets.New(podIdentifiers...))
 	if err != nil {
+		tracing.SetSpanError(span, err)
 		return nil, fmt.Errorf("failed to query kvblock indexer: %w", err)
 	}
 	traceLogger.Info("found block keys", "block-keys", blockKeys,
 		"pods", podsPerKeyPrintHelper(keyToPods))
 
 	// 4. score pods
+	ctx, scorePodSpan := tracing.StartSpan(ctx, "kv-cache-manager.ScorePods", tracing.OperationScorePods)
 	podScores, err := k.kvBlockScorer.Score(strBlockKeys, keyToPods)
 	if err != nil {
+		tracing.SetSpanError(scorePodSpan, err)
+		scorePodSpan.End()
+		tracing.SetSpanError(span, err)
 		return nil, fmt.Errorf("failed to query kvblock scorer: %w", err)
 	}
+	tracing.SetSpanError(scorePodSpan, nil)
+	scorePodSpan.End()
 	traceLogger.Info("found pod scores", "pod-scores", podScores)
 
+	// Calculate hit ratio for observability
+	totalPods := len(podIdentifiers)
+	if totalPods == 0 {
+		// If no specific pods requested, use all pods with scores
+		totalPods = len(podScores)
+	}
+
+	var hitRatio float64
+	if totalPods > 0 {
+		hitRatio = float64(len(podScores)) / float64(totalPods)
+	}
+
+	span.SetAttributes(
+		attribute.Float64(tracing.AttrKVCacheHitRatio, hitRatio),
+		attribute.String(tracing.AttrOperationOutcome, tracing.OutcomeSuccess),
+	)
+
 	return podScores, nil
 }
 

pkg/kvcache/kvblock/index.go

@@ -46,6 +46,7 @@ type IndexConfig struct {
 func DefaultIndexConfig() *IndexConfig {
 	return &IndexConfig{
 		InMemoryConfig: DefaultInMemoryIndexConfig(),
+		RedisConfig:    DefaultRedisIndexConfig(),
 		EnableMetrics:  false,
 	}
 }

pkg/kvcache/kvblock/redis.go

@@ -23,6 +23,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/redis/go-redis/extra/redisotel/v9"
 	"github.com/redis/go-redis/v9"
 	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/klog/v2"
@@ -57,6 +58,17 @@ func NewRedisIndex(config *RedisIndexConfig) (Index, error) {
 	}
 
 	redisClient := redis.NewClient(redisOpt)
+
+	// Enable automatic OpenTelemetry tracing for Redis operations
+	if err := redisotel.InstrumentTracing(redisClient); err != nil {
+		return nil, fmt.Errorf("failed to instrument Redis tracing: %w", err)
+	}
+
+	// Enable automatic OpenTelemetry metrics for Redis operations
+	if err := redisotel.InstrumentMetrics(redisClient); err != nil {
+		return nil, fmt.Errorf("failed to instrument Redis metrics: %w", err)
+	}
+
 	if err := redisClient.Ping(context.Background()).Err(); err != nil {
 		return nil, fmt.Errorf("failed to connect to Redis: %w", err)
 	}
@@ -110,6 +122,7 @@ func (r *RedisIndex) Lookup(ctx context.Context, keys []Key,
 
 	filterPods := len(podIdentifierSet) > 0 // predicate for filtering
 	highestHitIdx := 0
+	totalPodsFound := 0
 
 	for idx, cmd := range results {
 		key := keys[idx]
@@ -138,6 +151,7 @@ func (r *RedisIndex) Lookup(ctx context.Context, keys []Key,
 		}
 
 		highestHitIdx = idx
+		totalPodsFound += len(filteredPods)
 		podsPerKey[key] = filteredPods
 	}