Files
ollama/server/prompt_test.go
Jeffrey Morgan df70249520 server: optimize chatPrompt to reduce tokenization calls (#14040)
Change the truncation algorithm to start with all messages and remove
from the front until it fits, rather than adding messages one at a time
from the back. This reduces tokenization calls from O(n) to O(1) in the
common case where all messages fit in context.
2026-02-04 01:21:31 -08:00

333 lines
9.9 KiB
Go

package server
import (
"bytes"
"context"
"testing"
"github.com/google/go-cmp/cmp"
"github.com/ollama/ollama/api"
"github.com/ollama/ollama/template"
)
func TestChatPrompt(t *testing.T) {
type expect struct {
prompt string
images [][]byte
error error
}
tmpl, err := template.Parse(`
{{- if .System }}{{ .System }} {{ end }}
{{- if .Prompt }}{{ .Prompt }} {{ end }}
{{- if .Response }}{{ .Response }} {{ end }}`)
if err != nil {
t.Fatal(err)
}
visionModel := Model{Template: tmpl, ProjectorPaths: []string{"vision"}}
cases := []struct {
name string
model Model
limit int
truncate bool
msgs []api.Message
expect
}{
{
name: "messages",
model: visionModel,
limit: 64,
truncate: true,
msgs: []api.Message{
{Role: "user", Content: "You're a test, Harry!"},
{Role: "assistant", Content: "I-I'm a what?"},
{Role: "user", Content: "A test. And a thumping good one at that, I'd wager."},
},
expect: expect{
prompt: "You're a test, Harry! I-I'm a what? A test. And a thumping good one at that, I'd wager. ",
},
},
{
name: "truncate messages",
model: visionModel,
limit: 1,
truncate: true,
msgs: []api.Message{
{Role: "user", Content: "You're a test, Harry!"},
{Role: "assistant", Content: "I-I'm a what?"},
{Role: "user", Content: "A test. And a thumping good one at that, I'd wager."},
},
expect: expect{
prompt: "A test. And a thumping good one at that, I'd wager. ",
},
},
{
name: "truncate messages with image",
model: visionModel,
limit: 64,
truncate: true,
msgs: []api.Message{
{Role: "user", Content: "You're a test, Harry!"},
{Role: "assistant", Content: "I-I'm a what?"},
{Role: "user", Content: "A test. And a thumping good one at that, I'd wager.", Images: []api.ImageData{[]byte("something")}},
},
expect: expect{
prompt: "[img-0]A test. And a thumping good one at that, I'd wager. ",
images: [][]byte{
[]byte("something"),
},
},
},
{
name: "truncate messages with images",
model: visionModel,
limit: 64,
truncate: true,
msgs: []api.Message{
{Role: "user", Content: "You're a test, Harry!", Images: []api.ImageData{[]byte("something")}},
{Role: "assistant", Content: "I-I'm a what?"},
{Role: "user", Content: "A test. And a thumping good one at that, I'd wager.", Images: []api.ImageData{[]byte("somethingelse")}},
},
expect: expect{
prompt: "[img-0]A test. And a thumping good one at that, I'd wager. ",
images: [][]byte{
[]byte("somethingelse"),
},
},
},
{
name: "messages with images",
model: visionModel,
limit: 2048,
truncate: true,
msgs: []api.Message{
{Role: "user", Content: "You're a test, Harry!", Images: []api.ImageData{[]byte("something")}},
{Role: "assistant", Content: "I-I'm a what?"},
{Role: "user", Content: "A test. And a thumping good one at that, I'd wager.", Images: []api.ImageData{[]byte("somethingelse")}},
},
expect: expect{
prompt: "[img-0]You're a test, Harry! I-I'm a what? [img-1]A test. And a thumping good one at that, I'd wager. ",
images: [][]byte{
[]byte("something"),
[]byte("somethingelse"),
},
},
},
{
name: "message with image tag",
model: visionModel,
limit: 2048,
truncate: true,
msgs: []api.Message{
{Role: "user", Content: "You're a test, Harry! [img]", Images: []api.ImageData{[]byte("something")}},
{Role: "assistant", Content: "I-I'm a what?"},
{Role: "user", Content: "A test. And a thumping good one at that, I'd wager.", Images: []api.ImageData{[]byte("somethingelse")}},
},
expect: expect{
prompt: "You're a test, Harry! [img-0] I-I'm a what? [img-1]A test. And a thumping good one at that, I'd wager. ",
images: [][]byte{
[]byte("something"),
[]byte("somethingelse"),
},
},
},
{
name: "messages with interleaved images",
model: visionModel,
limit: 2048,
truncate: true,
msgs: []api.Message{
{Role: "user", Content: "You're a test, Harry!"},
{Role: "user", Images: []api.ImageData{[]byte("something")}},
{Role: "user", Images: []api.ImageData{[]byte("somethingelse")}},
{Role: "assistant", Content: "I-I'm a what?"},
{Role: "user", Content: "A test. And a thumping good one at that, I'd wager."},
},
expect: expect{
prompt: "You're a test, Harry!\n\n[img-0]\n\n[img-1] I-I'm a what? A test. And a thumping good one at that, I'd wager. ",
images: [][]byte{
[]byte("something"),
[]byte("somethingelse"),
},
},
},
{
name: "truncate message with interleaved images",
model: visionModel,
limit: 1024,
truncate: true,
msgs: []api.Message{
{Role: "user", Content: "You're a test, Harry!"},
{Role: "user", Images: []api.ImageData{[]byte("something")}},
{Role: "user", Images: []api.ImageData{[]byte("somethingelse")}},
{Role: "assistant", Content: "I-I'm a what?"},
{Role: "user", Content: "A test. And a thumping good one at that, I'd wager."},
},
expect: expect{
prompt: "[img-0] I-I'm a what? A test. And a thumping good one at that, I'd wager. ",
images: [][]byte{
[]byte("somethingelse"),
},
},
},
{
name: "message with system prompt",
model: visionModel,
limit: 2048,
truncate: true,
msgs: []api.Message{
{Role: "system", Content: "You are the Test Who Lived."},
{Role: "user", Content: "You're a test, Harry!"},
{Role: "assistant", Content: "I-I'm a what?"},
{Role: "user", Content: "A test. And a thumping good one at that, I'd wager."},
},
expect: expect{
prompt: "You are the Test Who Lived. You're a test, Harry! I-I'm a what? A test. And a thumping good one at that, I'd wager. ",
},
},
{
name: "out of order system",
model: visionModel,
limit: 2048,
truncate: true,
msgs: []api.Message{
{Role: "user", Content: "You're a test, Harry!"},
{Role: "assistant", Content: "I-I'm a what?"},
{Role: "system", Content: "You are the Test Who Lived."},
{Role: "user", Content: "A test. And a thumping good one at that, I'd wager."},
},
expect: expect{
prompt: "You're a test, Harry! I-I'm a what? You are the Test Who Lived. A test. And a thumping good one at that, I'd wager. ",
},
},
{
name: "multiple images same prompt",
model: visionModel,
limit: 2048,
truncate: true,
msgs: []api.Message{
{Role: "user", Content: "Compare these two pictures of hotdogs", Images: []api.ImageData{[]byte("one hotdog"), []byte("two hotdogs")}},
},
expect: expect{
prompt: "[img-0][img-1]Compare these two pictures of hotdogs ",
images: [][]byte{[]byte("one hotdog"), []byte("two hotdogs")},
},
},
{
name: "no truncate with limit exceeded",
model: visionModel,
limit: 10,
truncate: false,
msgs: []api.Message{
{Role: "user", Content: "You're a test, Harry!"},
{Role: "assistant", Content: "I-I'm a what?"},
{Role: "user", Content: "A test. And a thumping good one at that, I'd wager."},
},
expect: expect{
prompt: "You're a test, Harry! I-I'm a what? A test. And a thumping good one at that, I'd wager. ",
},
},
}
for _, tt := range cases {
t.Run(tt.name, func(t *testing.T) {
model := tt.model
opts := api.Options{Runner: api.Runner{NumCtx: tt.limit}}
think := false
prompt, images, err := chatPrompt(t.Context(), &model, mockRunner{}.Tokenize, &opts, tt.msgs, nil, &api.ThinkValue{Value: think}, tt.truncate)
if tt.error == nil && err != nil {
t.Fatal(err)
} else if tt.error != nil && err != tt.error {
t.Fatalf("expected err '%q', got '%q'", tt.error, err)
}
if diff := cmp.Diff(prompt, tt.prompt); diff != "" {
t.Errorf("mismatch (-got +want):\n%s", diff)
}
if len(images) != len(tt.images) {
t.Fatalf("expected %d images, got %d", len(tt.images), len(images))
}
for i := range images {
if images[i].ID != i {
t.Errorf("expected ID %d, got %d", i, images[i].ID)
}
if len(model.Config.ModelFamilies) == 0 {
if !bytes.Equal(images[i].Data, tt.images[i]) {
t.Errorf("expected %q, got %q", tt.images[i], images[i].Data)
}
}
}
})
}
}
func TestChatPromptTokenizeCalls(t *testing.T) {
tmpl, err := template.Parse(`
{{- if .System }}{{ .System }} {{ end }}
{{- if .Prompt }}{{ .Prompt }} {{ end }}
{{- if .Response }}{{ .Response }} {{ end }}`)
if err != nil {
t.Fatal(err)
}
model := Model{Template: tmpl}
cases := []struct {
name string
limit int
msgs []api.Message
maxTokenizes int
}{
{
name: "all messages fit",
limit: 2048,
msgs: []api.Message{
{Role: "user", Content: "message 1"},
{Role: "assistant", Content: "response 1"},
{Role: "user", Content: "message 2"},
{Role: "assistant", Content: "response 2"},
{Role: "user", Content: "message 3"},
},
maxTokenizes: 1,
},
{
name: "truncate to last message",
limit: 5,
msgs: []api.Message{
{Role: "user", Content: "message 1"},
{Role: "assistant", Content: "response 1"},
{Role: "user", Content: "message 2"},
{Role: "assistant", Content: "response 2"},
{Role: "user", Content: "message 3"},
},
maxTokenizes: 5,
},
}
for _, tt := range cases {
t.Run(tt.name, func(t *testing.T) {
tokenizeCount := 0
countingTokenize := func(ctx context.Context, s string) ([]int, error) {
tokenizeCount++
tokens, err := mockRunner{}.Tokenize(ctx, s)
return tokens, err
}
opts := api.Options{Runner: api.Runner{NumCtx: tt.limit}}
think := false
_, _, err := chatPrompt(t.Context(), &model, countingTokenize, &opts, tt.msgs, nil, &api.ThinkValue{Value: think}, true)
if err != nil {
t.Fatal(err)
}
if tokenizeCount > tt.maxTokenizes {
t.Errorf("tokenize called %d times, expected at most %d", tokenizeCount, tt.maxTokenizes)
}
})
}
}