delay TTL check until after all requests are complete (#25)

- fixes #25 where requests that last longer than the TTL will cause the
  process to be unloaded before the next request.
- new behavior, TTL waits until all requests are complete before
  checking timeout

README.md

@@ -2,20 +2,32 @@
 
 ![llama-swap header image](header.jpeg)
 
-llama-swap is a golang server that automatically swaps the llama.cpp server on demand. Since [llama.cpp's server](https://github.com/ggerganov/llama.cpp/tree/master/examples/server) can't swap models, let's swap the server instead!
+# Introduction
+llama-swap is an OpenAI API compatible server that gives you complete control over how you use your hardware. It automatically swaps to the configuration of your choice for serving a model. Since [llama.cpp's server](https://github.com/ggerganov/llama.cpp/tree/master/examples/server) can't swap models, let's swap the server instead!
 
 Features:
 
 - ✅ Easy to deploy: single binary with no dependencies
 - ✅ Single yaml configuration file
-- ✅ Automatic switching between models
-- ✅ Full control over llama.cpp server settings per model
+- ✅ On-demand model switching
+- ✅ Full control over server settings per model
 - ✅ OpenAI API support (`v1/completions` and `v1/chat/completions`)
 - ✅ Multiple GPU support
 - ✅ Run multiple models at once with `profiles`
 - ✅ Remote log monitoring at `/log`
 - ✅ Automatic unloading of models from GPUs after timeout
 
+## Releases
+
+Builds for Linux and OSX are available on the [Releases](https://github.com/mostlygeek/llama-swap/releases) page.
+
+### Building from source
+
+1. Install golang for your system
+1. `git clone git@github.com:mostlygeek/llama-swap.git`
+1. `make clean all`
+1. Binaries will be in `build/` subdirectory
+
 ## config.yaml
 
 llama-swap's configuration is purposefully simple.
@@ -64,7 +76,7 @@ models:
 #
 # Tips:
 #  - each model must be listening on a unique address and port
-#  - the model name is in this format: "profile_name/model", like "coding/qwen"
+#  - the model name is in this format: "profile_name:model", like "coding:qwen"
 #  - the profile will load and unload all models in the profile at the same time
 profiles:
   coding:
@@ -83,22 +95,22 @@ More [examples](examples/README.md) are available for different use cases.
 
 ## Monitoring Logs
 
-The `/logs` endpoint is available to monitor what llama-swap is doing. It will send the last 10KB of logs. Useful for monitoring the output of llama-server. It also supports streaming of logs.
+Open the `http://<host>/logs` with your browser to get a web interface with streaming logs.
 
-Usage:
+Of course, CLI access is also supported:
 
 ```
 # sends up to the last 10KB of logs
 curl http://host/logs'
 
-# streams logs using chunk encoding
+# streams logs
 curl -Ns 'http://host/logs/stream'
 
+# stream and filter logs with linux pipes
+curl -Ns http://host/logs/stream | grep 'eval time'
+
 # skips history and just streams new log entries
 curl -Ns 'http://host/logs/stream?no-history'
-
-# streams logs using Server Sent Events
-curl -Ns 'http://host/logs/streamSSE'
 ```
 
 ## Systemd Unit Files
@@ -125,9 +137,3 @@ StartLimitInterval=30
 [Install]
 WantedBy=multi-user.target
 ```
-
-## Building from Source
-
-1. Install golang for your system
-1. run `make clean all`
-1. binaries will be built into `build/` directory

examples/README.md

@@ -1,9 +1,6 @@
-# Example Configurations
+# Example Configs and Use Cases
 
-Learning by example is best.
-
-Here in the `examples/` folder are llama-swap configurations that can be used on your local LLM server.
-
-## List
+A collections of usecases and examples for getting the most out of llama-swap.
 
 * [Speculative Decoding](speculative-decoding/README.md) - using a small draft model can increase inference speeds from 20% to 40%. This example includes a configurations Qwen2.5-Coder-32B (2.5x increase) and Llama-3.1-70B (1.4x increase) in the best cases.
+* [Optimizing Code Generation](benchmark-snakegame/README.md) - find the optimal settings for your machine. This example demonstrates defining multiple configurations and testing which one is fastest.

examples/benchmark-snakegame/README.md

@@ -0,0 +1,123 @@
+# Optimizing Code Generation with llama-swap
+
+Finding the best mix of settings for your hardware can be time consuming. This example demonstrates using a custom configuration file to automate testing different scenarios to find the an optimal configuration.
+
+The benchmark writes a snake game in Python, TypeScript, and Swift using the Qwen 2.5 Coder models. The experiments were done using a 3090 and a P40.
+
+**Benchmark Scenarios**
+
+Three scenarios are tested:
+
+- 3090-only: Just the main model on the 3090
+- 3090-with-draft: the main and draft models on the 3090
+- 3090-P40-draft: the main model on the 3090 with the draft model offloaded to the P40
+
+**Available Devices**
+
+Use the following command to list available devices IDs for the configuration:
+
+```
+$ /mnt/nvme/llama-server/llama-server-f3252055 --list-devices
+ggml_cuda_init: GGML_CUDA_FORCE_MMQ:    no
+ggml_cuda_init: GGML_CUDA_FORCE_CUBLAS: no
+ggml_cuda_init: found 4 CUDA devices:
+  Device 0: NVIDIA GeForce RTX 3090, compute capability 8.6, VMM: yes
+  Device 1: Tesla P40, compute capability 6.1, VMM: yes
+  Device 2: Tesla P40, compute capability 6.1, VMM: yes
+  Device 3: Tesla P40, compute capability 6.1, VMM: yes
+Available devices:
+  CUDA0: NVIDIA GeForce RTX 3090 (24154 MiB, 406 MiB free)
+  CUDA1: Tesla P40 (24438 MiB, 22942 MiB free)
+  CUDA2: Tesla P40 (24438 MiB, 24144 MiB free)
+  CUDA3: Tesla P40 (24438 MiB, 24144 MiB free)
+```
+
+**Configuration**
+
+The configuration file, `benchmark-config.yaml`, defines the three scenarios:
+
+```yaml
+models:
+  "3090-only":
+    proxy: "http://127.0.0.1:9503"
+    cmd: >
+      /mnt/nvme/llama-server/llama-server-f3252055
+      --host 127.0.0.1 --port 9503
+      --flash-attn
+      --slots
+
+      --model /mnt/nvme/models/Qwen2.5-Coder-32B-Instruct-Q4_K_M.gguf
+      -ngl 99
+      --device CUDA0
+
+      --ctx-size 32768
+      --cache-type-k q8_0 --cache-type-v q8_0
+
+  "3090-with-draft":
+    proxy: "http://127.0.0.1:9503"
+    # --ctx-size 28500 max that can fit on 3090 after draft model
+    cmd: >
+      /mnt/nvme/llama-server/llama-server-f3252055
+      --host 127.0.0.1 --port 9503
+      --flash-attn
+      --slots
+
+      --model /mnt/nvme/models/Qwen2.5-Coder-32B-Instruct-Q4_K_M.gguf
+      -ngl 99
+      --device CUDA0
+
+      --model-draft /mnt/nvme/models/Qwen2.5-Coder-0.5B-Instruct-Q8_0.gguf
+      -ngld 99
+      --draft-max 16
+      --draft-min 4
+      --draft-p-min 0.4
+      --device-draft CUDA0
+
+      --ctx-size 28500
+      --cache-type-k q8_0 --cache-type-v q8_0
+
+  "3090-P40-draft":
+    proxy: "http://127.0.0.1:9503"
+    cmd: >
+      /mnt/nvme/llama-server/llama-server-f3252055
+      --host 127.0.0.1 --port 9503
+      --flash-attn --metrics
+      --slots
+      --model /mnt/nvme/models/Qwen2.5-Coder-32B-Instruct-Q4_K_M.gguf
+      -ngl 99
+      --device CUDA0
+
+      --model-draft /mnt/nvme/models/Qwen2.5-Coder-0.5B-Instruct-Q8_0.gguf
+      -ngld 99
+      --draft-max 16
+      --draft-min 4
+      --draft-p-min 0.4
+      --device-draft CUDA1
+
+      --ctx-size 32768
+      --cache-type-k q8_0 --cache-type-v q8_0
+```
+
+> Note in the `3090-with-draft` scenario the `--ctx-size` had to be reduced from 32768 to to accommodate the draft model.
+
+
+**Running the Benchmark**
+
+To run the benchmark, execute the following commands:
+
+1. `llama-swap -config benchmark-config.yaml`
+1. `./run-benchmark.sh http://localhost:8080 "3090-only" "3090-with-draft" "3090-P40-draft"`
+
+The [benchmark script](run-benchmark.sh) generates a CSV output of the results, which can be converted to a Markdown table for readability.
+
+**Results (tokens/second)**
+
+| model           | python | typescript | swift |
+|-----------------|--------|------------|-------|
+| 3090-only       | 34.03  | 34.01      | 34.01 |
+| 3090-with-draft | 106.65 | 70.48      | 57.89 |
+| 3090-P40-draft  | 81.54  | 60.35      | 46.50 |
+
+Many different factors, like the programming language, can have big impacts on the performance gains. However, with a custom configuration file for benchmarking it is easy to test the different variations to discover what's best for your hardware.
+
+Happy coding!

examples/benchmark-snakegame/run-benchmark.sh

@@ -0,0 +1,40 @@
+#!/usr/bin/env bash
+
+# This script generates a CSV file showing the token/second for generating a Snake Game in python, typescript and swift
+# It was created to test the effects of speculative decoding and the various draft settings on performance.
+#
+# Writing code with a low temperature seems to provide fairly consistent logic.
+#
+# Usage: ./benchmark.sh <url> <model1> [model2 ...]
+# Example: ./benchmark.sh http://localhost:8080 model1 model2
+
+if [ "$#" -lt 2 ]; then
+    echo "Usage: $0 <url> <model1> [model2 ...]"
+    exit 1
+fi
+
+url=$1; shift
+
+echo "model,python,typescript,swift"
+
+for model in "$@"; do
+
+    echo -n "$model,"
+
+    for lang in "python" "typescript" "swift"; do
+        # expects a llama.cpp after PR https://github.com/ggerganov/llama.cpp/pull/10548
+        # (Dec 3rd/2024)
+        time=$(curl -s --url "$url/v1/chat/completions" -d "{\"messages\": [{\"role\": \"system\", \"content\": \"you only write code.\"}, {\"role\": \"user\", \"content\": \"write snake game in $lang\"}], \"top_k\": 1, \"timings_per_token\":true, \"model\":\"$model\"}" | jq -r .timings.predicted_per_second)
+
+        if [ $? -ne 0 ]; then
+            time="error"
+            exit 1
+        fi
+
+        if [ "$lang" != "swift" ]; then
+            printf "%0.2f tps," $time
+        else
+            printf "%0.2f tps\n" $time
+        fi
+    done
+done

proxy/html/logs.html

@@ -0,0 +1,53 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Logs</title>
+    <style>
+        body {
+            margin: 0;
+            height: 100vh;
+            display: flex;
+            flex-direction: column;
+            font-family: "Courier New", Courier, monospace;
+        }
+        #log-stream {
+            flex: 1;
+            margin: 1em;
+            padding: 10px;
+            background: #f4f4f4;
+            overflow-y: auto;
+            white-space: pre-wrap; /* Ensures line wrapping */
+            word-wrap: break-word; /* Ensures long words wrap */
+        }
+    </style>
+</head>
+<body>
+    <pre id="log-stream">Waiting for logs...
+</pre>
+
+    <script>
+        // Establish an EventSource connection to the SSE endpoint
+        if (typeof(EventSource) !== "undefined") {
+            const eventSource = new EventSource("/logs/streamSSE");
+
+            eventSource.onmessage = function(event) {
+                // Append the new log message to the <pre> element
+                const logStream = document.getElementById('log-stream');
+
+                logStream.textContent += event.data;
+
+                // Auto-scroll to the bottom
+                logStream.scrollTop = logStream.scrollHeight;
+            };
+
+            eventSource.onerror = function(err) {
+                console.error("EventSource failed:", err);
+            };
+        } else {
+            console.error("SSE not supported by this browser.");
+        }
+    </script>
+</body>
+</html>

proxy/process.go

@@ -122,16 +122,15 @@ func (p *Process) start() error {
 		// start a goroutine to check every second if
 		// the process should be stopped
 		go func() {
-			ticker := time.NewTicker(time.Second)
-			defer ticker.Stop()
 			maxDuration := time.Duration(p.config.UnloadAfter) * time.Second
 
-			for {
-				<-ticker.C
+			for range time.Tick(time.Second) {
+				// wait for all inflight requests to complete and ticker
+				p.inFlightRequests.Wait()
+
 				if time.Since(p.lastRequestHandled) > maxDuration {
 					fmt.Fprintf(p.logMonitor, "!!! Unloading model %s, TTL of %d reached.\n", p.ID, p.config.UnloadAfter)
 					p.Stop()
-					return
 				}
 			}
 		}()
@@ -275,7 +274,11 @@ func (p *Process) checkHealthEndpoint(ctxFromStart context.Context) error {
 func (p *Process) ProxyRequest(w http.ResponseWriter, r *http.Request) {
 
 	p.inFlightRequests.Add(1)
-	defer p.inFlightRequests.Done()
+
+	defer func() {
+		p.lastRequestHandled = time.Now()
+		p.inFlightRequests.Done()
+	}()
 
 	if p.CurrentState() != StateReady {
 		if err := p.start(); err != nil {
@@ -285,8 +288,6 @@ func (p *Process) ProxyRequest(w http.ResponseWriter, r *http.Request) {
 		}
 	}
 
-	p.lastRequestHandled = time.Now()
-
 	proxyTo := p.config.Proxy
 	client := &http.Client{}
 	req, err := http.NewRequest(r.Method, proxyTo+r.URL.String(), r.Body)

proxy/process_test.go

@@ -82,18 +82,31 @@ func TestProcess_UnloadAfterTTL(t *testing.T) {
 	process := NewProcess("ttl", 2, config, NewLogMonitorWriter(io.Discard))
 	defer process.Stop()
 
-	req := httptest.NewRequest("GET", "/test", nil)
+	// this should take 4 seconds
+	req1 := httptest.NewRequest("GET", "/slow-respond?echo=1234&delay=1000ms", nil)
+	req2 := httptest.NewRequest("GET", "/test", nil)
+
 	w := httptest.NewRecorder()
 
-	// Proxy the request (auto start)
-	process.ProxyRequest(w, req)
+	// Proxy the request (auto start) with a slow response that takes longer than config.UnloadAfter
+	process.ProxyRequest(w, req1)
 
+	t.Log("sending slow first request (4 seconds)")
+	assert.Equal(t, http.StatusOK, w.Code, "Expected status code %d, got %d", http.StatusOK, w.Code)
+	assert.Contains(t, w.Body.String(), "1234")
+	assert.Equal(t, StateReady, process.CurrentState())
+
+	// ensure the TTL timeout does not race slow requests (see issue #25)
+	t.Log("sending second request (1 second)")
+	time.Sleep(time.Second)
+	w = httptest.NewRecorder()
+	process.ProxyRequest(w, req2)
 	assert.Equal(t, http.StatusOK, w.Code, "Expected status code %d, got %d", http.StatusOK, w.Code)
 	assert.Contains(t, w.Body.String(), expectedMessage)
-
 	assert.Equal(t, StateReady, process.CurrentState())
 
 	// wait 5 seconds
+	t.Log("sleep 5 seconds and check if unloaded")
 	time.Sleep(5 * time.Second)
 	assert.Equal(t, StateStopped, process.CurrentState())
 }
@@ -101,7 +114,7 @@ func TestProcess_UnloadAfterTTL(t *testing.T) {
 // issue #19
 func TestProcess_HTTPRequestsHaveTimeToFinish(t *testing.T) {
 	if testing.Short() {
-		t.Skip("skipping long test")
+		t.Skip("skipping slow test")
 	}
 
 	expectedMessage := "12345"

proxy/proxymanager.go

@@ -98,6 +98,10 @@ func (pm *ProxyManager) listModelsHandler(c *gin.Context) {
 	// Set the Content-Type header to application/json
 	c.Header("Content-Type", "application/json")
 
+	if origin := c.Request.Header.Get("Origin"); origin != "" {
+		c.Header("Access-Control-Allow-Origin", origin)
+	}
+
 	// Encode the data as JSON and write it to the response writer
 	if err := json.NewEncoder(c.Writer).Encode(map[string]interface{}{"data": data}); err != nil {
 		c.AbortWithError(http.StatusInternalServerError, fmt.Errorf("error encoding JSON"))

proxy/proxymanager_loghandlers.go

@@ -1,19 +1,41 @@
 package proxy
 
 import (
+	"embed"
 	"fmt"
 	"net/http"
+	"strings"
 
 	"github.com/gin-gonic/gin"
 )
 
+//go:embed html/logs.html
+var logsHTML []byte
+
+// make sure embed is kept there by the IDE auto-package importer
+var _ = embed.FS{}
+
 func (pm *ProxyManager) sendLogsHandlers(c *gin.Context) {
-	c.Header("Content-Type", "text/plain")
-	history := pm.logMonitor.GetHistory()
-	_, err := c.Writer.Write(history)
-	if err != nil {
-		c.AbortWithError(http.StatusInternalServerError, err)
-		return
+
+	accept := c.GetHeader("Accept")
+	if strings.Contains(accept, "text/html") {
+		// Set the Content-Type header to text/html
+		c.Header("Content-Type", "text/html")
+
+		// Write the embedded HTML content to the response
+		_, err := c.Writer.Write(logsHTML)
+		if err != nil {
+			c.AbortWithError(http.StatusInternalServerError, fmt.Errorf("failed to write response: %v", err))
+			return
+		}
+	} else {
+		c.Header("Content-Type", "text/plain")
+		history := pm.logMonitor.GetHistory()
+		_, err := c.Writer.Write(history)
+		if err != nil {
+			c.AbortWithError(http.StatusInternalServerError, err)
+			return
+		}
 	}
 }
 

proxy/proxymanager_test.go

@@ -2,6 +2,7 @@ package proxy
 
 import (
 	"bytes"
+	"encoding/json"
 	"fmt"
 	"net/http"
 	"net/http/httptest"
@@ -141,3 +142,71 @@ func TestProxyManager_SwapMultiProcessParallelRequests(t *testing.T) {
 		assert.Equal(t, key, result)
 	}
 }
+
+func TestProxyManager_ListModelsHandler(t *testing.T) {
+	config := &Config{
+		HealthCheckTimeout: 15,
+		Models: map[string]ModelConfig{
+			"model1": getTestSimpleResponderConfig("model1"),
+			"model2": getTestSimpleResponderConfig("model2"),
+			"model3": getTestSimpleResponderConfig("model3"),
+		},
+	}
+
+	proxy := New(config)
+
+	// Create a test request
+	req := httptest.NewRequest("GET", "/v1/models", nil)
+	req.Header.Add("Origin", "i-am-the-origin")
+	w := httptest.NewRecorder()
+
+	// Call the listModelsHandler
+	proxy.HandlerFunc(w, req)
+
+	// Check the response status code
+	assert.Equal(t, http.StatusOK, w.Code)
+
+	// Check for Access-Control-Allow-Origin
+	assert.Equal(t, req.Header.Get("Origin"), w.Result().Header.Get("Access-Control-Allow-Origin"))
+
+	// Parse the JSON response
+	var response struct {
+		Data []map[string]interface{} `json:"data"`
+	}
+	if err := json.Unmarshal(w.Body.Bytes(), &response); err != nil {
+		t.Fatalf("Failed to parse JSON response: %v", err)
+	}
+
+	// Check the number of models returned
+	assert.Len(t, response.Data, 3)
+
+	// Check the details of each model
+	expectedModels := map[string]struct{}{
+		"model1": {},
+		"model2": {},
+		"model3": {},
+	}
+
+	for _, model := range response.Data {
+		modelID, ok := model["id"].(string)
+		assert.True(t, ok, "model ID should be a string")
+		_, exists := expectedModels[modelID]
+		assert.True(t, exists, "unexpected model ID: %s", modelID)
+		delete(expectedModels, modelID)
+
+		object, ok := model["object"].(string)
+		assert.True(t, ok, "object should be a string")
+		assert.Equal(t, "model", object)
+
+		created, ok := model["created"].(float64)
+		assert.True(t, ok, "created should be a number")
+		assert.Greater(t, created, float64(0)) // Assuming the timestamp is positive
+
+		ownedBy, ok := model["owned_by"].(string)
+		assert.True(t, ok, "owned_by should be a string")
+		assert.Equal(t, "llama-swap", ownedBy)
+	}
+
+	// Ensure all expected models were returned
+	assert.Empty(t, expectedModels, "not all expected models were returned")
+}