sklears_compose/execution/
engine.rs

1//! Core execution engine implementation
2//!
3//! This module provides the main `ComposableExecutionEngine` and its core functionality.
4
5use sklears_core::{
6    error::{Result as SklResult, SklearsError},
7    traits::Estimator,
8};
9use std::any::Any;
10use std::collections::{HashMap, VecDeque};
11use std::sync::{Arc, Mutex, RwLock};
12use std::time::{Duration, Instant};
13
14use super::config::{ExecutionEngineConfig, ResourceConstraints, StrategyConfig};
15
16/// Composable execution engine that can be configured with different strategies
17pub struct ComposableExecutionEngine {
18    /// Engine configuration
19    config: ExecutionEngineConfig,
20    /// Active execution strategies
21    strategies: HashMap<String, Box<dyn ExecutionStrategy>>,
22    /// Resource manager
23    resource_manager: Arc<ResourceManager>,
24    /// Task scheduler
25    scheduler: Box<dyn TaskScheduler>,
26    /// Execution context
27    context: ExecutionContext,
28    /// Metrics collector
29    metrics: Arc<Mutex<ExecutionMetrics>>,
30}
31
32/// Execution context for maintaining state during execution
33#[derive(Debug, Clone)]
34pub struct ExecutionContext {
35    /// Context ID
36    pub id: String,
37    /// Current execution phase
38    pub phase: ExecutionPhase,
39    /// Execution metadata
40    pub metadata: HashMap<String, String>,
41    /// Resource usage
42    pub resource_usage: ResourceUsage,
43    /// Start time
44    pub start_time: Instant,
45}
46
47/// Current execution phase
48#[derive(Debug, Clone, PartialEq)]
49pub enum ExecutionPhase {
50    /// Initializing
51    Initializing,
52    /// Planning
53    Planning,
54    /// Executing
55    Executing,
56    /// Monitoring
57    Monitoring,
58    /// Completed
59    Completed,
60    /// Failed
61    Failed,
62}
63
64/// Current resource usage
65#[derive(Debug, Clone)]
66pub struct ResourceUsage {
67    /// CPU usage percentage (0-100)
68    pub cpu_usage: f64,
69    /// Memory usage in bytes
70    pub memory_usage: u64,
71    /// Active tasks count
72    pub active_tasks: usize,
73    /// I/O operations per second
74    pub io_ops: u64,
75}
76
77/// Execution strategy trait for pluggable execution behaviors
78pub trait ExecutionStrategy: Send + Sync {
79    /// Strategy name
80    fn name(&self) -> &str;
81
82    /// Execute a task with this strategy
83    fn execute(
84        &self,
85        task: &dyn ExecutableTask,
86        context: &ExecutionContext,
87    ) -> SklResult<ExecutionResult>;
88
89    /// Check if strategy can handle the given task
90    fn can_handle(&self, task: &dyn ExecutableTask) -> bool;
91
92    /// Get strategy configuration
93    fn config(&self) -> &StrategyConfig;
94
95    /// Clone the strategy
96    fn clone_strategy(&self) -> Box<dyn ExecutionStrategy>;
97}
98
99/// Task that can be executed by the engine
100pub trait ExecutableTask: Send + Sync {
101    /// Task identifier
102    fn id(&self) -> &str;
103
104    /// Task type
105    fn task_type(&self) -> &str;
106
107    /// Execute the task
108    fn execute(&self) -> SklResult<TaskResult>;
109
110    /// Estimate resource requirements
111    fn resource_estimate(&self) -> ResourceEstimate;
112
113    /// Get task dependencies
114    fn dependencies(&self) -> Vec<String>;
115}
116
117/// Result of task execution
118#[derive(Debug)]
119pub struct TaskResult {
120    /// Task ID
121    pub task_id: String,
122    /// Execution status
123    pub status: TaskStatus,
124    /// Result data
125    pub data: Option<Box<dyn Any + Send>>,
126    /// Execution duration
127    pub duration: Duration,
128    /// Resource usage during execution
129    pub resource_usage: ResourceUsage,
130}
131
132/// Task execution status
133#[derive(Debug, Clone, PartialEq)]
134pub enum TaskStatus {
135    /// Pending
136    Pending,
137    /// Running
138    Running,
139    /// Completed
140    Completed,
141    /// Failed
142    Failed,
143    /// Cancelled
144    Cancelled,
145}
146
147/// Resource estimation for a task
148#[derive(Debug, Clone)]
149pub struct ResourceEstimate {
150    /// Estimated CPU cores needed
151    pub cpu_cores: f64,
152    /// Estimated memory usage in bytes
153    pub memory_bytes: u64,
154    /// Estimated execution time
155    pub execution_time: Duration,
156    /// Estimated I/O operations
157    pub io_operations: u64,
158}
159
160/// Result of execution strategy
161#[derive(Debug)]
162pub struct ExecutionResult {
163    /// Strategy that executed the task
164    pub strategy_name: String,
165    /// Task result
166    pub task_result: TaskResult,
167    /// Execution metadata
168    pub metadata: HashMap<String, String>,
169}
170
171/// Task scheduler trait for managing task execution order
172pub trait TaskScheduler: Send + Sync {
173    /// Add a task to the schedule
174    fn schedule_task(&mut self, task: Box<dyn ExecutableTask>) -> SklResult<()>;
175
176    /// Get the next task to execute
177    fn next_task(&mut self) -> Option<Box<dyn ExecutableTask>>;
178
179    /// Get current queue size
180    fn queue_size(&self) -> usize;
181
182    /// Set scheduler configuration
183    fn set_config(&mut self, config: SchedulerConfig);
184}
185
186/// Scheduler configuration
187#[derive(Debug, Clone)]
188pub struct SchedulerConfig {
189    /// Scheduling algorithm
190    pub algorithm: SchedulingAlgorithm,
191    /// Priority weights
192    pub priority_weights: HashMap<String, f64>,
193    /// Resource-aware scheduling
194    pub resource_aware: bool,
195}
196
197/// Available scheduling algorithms
198#[derive(Debug, Clone)]
199pub enum SchedulingAlgorithm {
200    /// FIFO
201    FIFO,
202    /// Priority
203    Priority,
204    /// ShortestJobFirst
205    ShortestJobFirst,
206    /// ResourceAware
207    ResourceAware,
208    /// DeadlineAware
209    DeadlineAware,
210}
211
212/// Resource manager for controlling resource usage
213pub struct ResourceManager {
214    /// Current resource allocations
215    allocations: Arc<RwLock<HashMap<String, ResourceAllocation>>>,
216    /// Resource constraints
217    constraints: ResourceConstraints,
218    /// Resource monitor
219    monitor: Arc<ResourceMonitor>,
220}
221
222/// Resource allocation for a specific consumer
223#[derive(Debug, Clone)]
224pub struct ResourceAllocation {
225    /// Consumer ID
226    pub consumer_id: String,
227    /// Allocated CPU cores
228    pub cpu_cores: f64,
229    /// Allocated memory in bytes
230    pub memory_bytes: u64,
231    /// Allocation timestamp
232    pub allocated_at: Instant,
233}
234
235/// Resource monitor for tracking usage
236pub struct ResourceMonitor {
237    /// Resource usage history
238    usage_history: Arc<RwLock<VecDeque<ResourceSnapshot>>>,
239    /// Monitoring interval
240    interval: Duration,
241}
242
243/// Snapshot of resource usage at a point in time
244#[derive(Debug, Clone)]
245pub struct ResourceSnapshot {
246    /// Timestamp of snapshot
247    pub timestamp: Instant,
248    /// CPU usage percentage
249    pub cpu_usage: f64,
250    /// Memory usage in bytes
251    pub memory_usage: u64,
252    /// Number of active tasks
253    pub active_tasks: usize,
254    /// I/O operations per second
255    pub io_rate: f64,
256}
257
258/// Metrics collector for execution statistics
259#[derive(Debug, Default, Clone)]
260pub struct ExecutionMetrics {
261    /// Total tasks executed
262    pub tasks_executed: u64,
263    /// Total execution time
264    pub total_execution_time: Duration,
265    /// Average task duration
266    pub average_task_duration: Duration,
267    /// Failed tasks count
268    pub failed_tasks: u64,
269    /// Resource utilization
270    pub resource_utilization: ResourceUtilization,
271}
272
273/// Resource utilization statistics
274#[derive(Debug, Default, Clone)]
275pub struct ResourceUtilization {
276    /// Average CPU usage
277    pub avg_cpu_usage: f64,
278    /// Peak CPU usage
279    pub peak_cpu_usage: f64,
280    /// Average memory usage
281    pub avg_memory_usage: u64,
282    /// Peak memory usage
283    pub peak_memory_usage: u64,
284}
285
286impl ComposableExecutionEngine {
287    /// Create a new execution engine with the given configuration
288    pub fn new(config: ExecutionEngineConfig) -> SklResult<Self> {
289        let resource_manager = Arc::new(ResourceManager::new(config.resource_constraints.clone()));
290        let scheduler = Box::new(DefaultTaskScheduler::new());
291        let context = ExecutionContext {
292            id: format!("ctx_{}", uuid::Uuid::new_v4()),
293            phase: ExecutionPhase::Initializing,
294            metadata: HashMap::new(),
295            resource_usage: ResourceUsage {
296                cpu_usage: 0.0,
297                memory_usage: 0,
298                active_tasks: 0,
299                io_ops: 0,
300            },
301            start_time: Instant::now(),
302        };
303
304        Ok(Self {
305            config,
306            strategies: HashMap::new(),
307            resource_manager,
308            scheduler,
309            context,
310            metrics: Arc::new(Mutex::new(ExecutionMetrics::default())),
311        })
312    }
313
314    /// Register a new execution strategy
315    pub fn register_strategy(&mut self, strategy: Box<dyn ExecutionStrategy>) {
316        let name = strategy.name().to_string();
317        self.strategies.insert(name, strategy);
318    }
319
320    /// Execute a task using the best available strategy
321    pub fn execute_task(&mut self, task: Box<dyn ExecutableTask>) -> SklResult<ExecutionResult> {
322        // Find the best strategy for this task
323        let strategy_name = self.select_strategy(&*task)?;
324
325        if let Some(strategy) = self.strategies.get(&strategy_name) {
326            // Update context
327            self.context.phase = ExecutionPhase::Executing;
328
329            // Execute the task
330            let result = strategy.execute(&*task, &self.context)?;
331
332            // Update metrics
333            self.update_metrics(&result);
334
335            // Update context
336            self.context.phase = ExecutionPhase::Completed;
337
338            Ok(result)
339        } else {
340            Err(SklearsError::InvalidInput(format!(
341                "Strategy '{strategy_name}' not found"
342            )))
343        }
344    }
345
346    /// Select the best strategy for a task
347    fn select_strategy(&self, task: &dyn ExecutableTask) -> SklResult<String> {
348        // Find strategies that can handle this task
349        let capable_strategies: Vec<_> = self
350            .strategies
351            .iter()
352            .filter(|(_, strategy)| strategy.can_handle(task))
353            .collect();
354
355        if capable_strategies.is_empty() {
356            return Err(SklearsError::InvalidInput(
357                "No capable strategy found for task".to_string(),
358            ));
359        }
360
361        // For now, select the first capable strategy
362        // TODO: Implement more sophisticated selection logic
363        Ok(capable_strategies[0].0.clone())
364    }
365
366    /// Update execution metrics
367    fn update_metrics(&self, result: &ExecutionResult) {
368        if let Ok(mut metrics) = self.metrics.lock() {
369            metrics.tasks_executed += 1;
370            metrics.total_execution_time += result.task_result.duration;
371
372            if result.task_result.status == TaskStatus::Failed {
373                metrics.failed_tasks += 1;
374            }
375
376            // Update average
377            metrics.average_task_duration = Duration::from_nanos(
378                metrics.total_execution_time.as_nanos() as u64 / metrics.tasks_executed,
379            );
380        }
381    }
382
383    /// Get current execution metrics
384    #[must_use]
385    pub fn metrics(&self) -> ExecutionMetrics {
386        self.metrics
387            .lock()
388            .unwrap_or_else(|e| e.into_inner())
389            .clone()
390    }
391
392    /// Get engine configuration
393    #[must_use]
394    pub fn config(&self) -> &ExecutionEngineConfig {
395        &self.config
396    }
397}
398
399impl ResourceManager {
400    /// Create a new resource manager
401    #[must_use]
402    pub fn new(constraints: ResourceConstraints) -> Self {
403        Self {
404            allocations: Arc::new(RwLock::new(HashMap::new())),
405            constraints,
406            monitor: Arc::new(ResourceMonitor::new(Duration::from_secs(1))),
407        }
408    }
409
410    /// Allocate resources for a consumer
411    pub fn allocate_resources(
412        &self,
413        consumer_id: String,
414        request: ResourceRequest,
415    ) -> SklResult<ResourceAllocation> {
416        let allocation = ResourceAllocation {
417            consumer_id: consumer_id.clone(),
418            cpu_cores: request.cpu_cores,
419            memory_bytes: request.memory_bytes,
420            allocated_at: Instant::now(),
421        };
422
423        if let Ok(mut allocations) = self.allocations.write() {
424            allocations.insert(consumer_id, allocation.clone());
425        }
426
427        Ok(allocation)
428    }
429}
430
431/// Resource request for allocation
432#[derive(Debug, Clone)]
433pub struct ResourceRequest {
434    /// Requested CPU cores
435    pub cpu_cores: f64,
436    /// Requested memory in bytes
437    pub memory_bytes: u64,
438    /// Request priority
439    pub priority: u32,
440}
441
442impl ResourceMonitor {
443    /// Create a new resource monitor
444    #[must_use]
445    pub fn new(interval: Duration) -> Self {
446        Self {
447            usage_history: Arc::new(RwLock::new(VecDeque::new())),
448            interval,
449        }
450    }
451}
452
453/// Default task scheduler implementation
454pub struct DefaultTaskScheduler {
455    /// Task queue
456    queue: VecDeque<Box<dyn ExecutableTask>>,
457    /// Scheduler configuration
458    config: SchedulerConfig,
459}
460
461impl Default for DefaultTaskScheduler {
462    fn default() -> Self {
463        Self::new()
464    }
465}
466
467impl DefaultTaskScheduler {
468    /// Create a new default scheduler
469    #[must_use]
470    pub fn new() -> Self {
471        Self {
472            queue: VecDeque::new(),
473            config: SchedulerConfig {
474                algorithm: SchedulingAlgorithm::FIFO,
475                priority_weights: HashMap::new(),
476                resource_aware: false,
477            },
478        }
479    }
480}
481
482impl TaskScheduler for DefaultTaskScheduler {
483    fn schedule_task(&mut self, task: Box<dyn ExecutableTask>) -> SklResult<()> {
484        self.queue.push_back(task);
485        Ok(())
486    }
487
488    fn next_task(&mut self) -> Option<Box<dyn ExecutableTask>> {
489        self.queue.pop_front()
490    }
491
492    fn queue_size(&self) -> usize {
493        self.queue.len()
494    }
495
496    fn set_config(&mut self, config: SchedulerConfig) {
497        self.config = config;
498    }
499}
sklears_compose/execution/engine.rs

sklears_compose/execution/
engine.rs
